Oct 282014




The use of three orthogonally tagged phosphine reagents to assist chemical work-up via phase-switch scavenging in conjunction with a modular flow reactor is described. These techniques (acidic, basic and Click chemistry) are used to prepare various amides and tri-substitutedguanidines from in situ generated iminophosphoranes.

Graphical abstract: Tagged phosphine reagents to assist reaction work-up by phase-switched scavenging using a modular flow reactor


Tagged Phosphine Reagents to Assist Reaction Work-up by Phase-Switched Scavenging Using a Modular Flow Reactor Process 

C.D. Smith, I.R. Baxendale, G.K. Tranmer, M. Baumann, S.C. Smith, R.A. Lewthwaite and S.V. Ley, Org. Biomol. Chem., 2007, 5, 1562-1568.


Oct 282014



 [3 + 2] Cycloaddition of Acetylenes with Azides to give 1,4-Disubstituted 1,2,3- Triazoles in a Modular Flow Reactor 

C.D. Smith, I.R. Baxendale, S. Lanners, J.J. Hayward, S.C. Smith and S.V. Ley, Org. Biomol. Chem. 2007, 5, 1559-1561.


The cycloaddition of acetylenes with azides to give the corresponding 1,4-disubstituted 1,2,3-triazoles is reported using immobilised reagents and scavengers in pre-packed glass tubes in a modular flow reactor.

Oct 272014




Deltamethrin is a pyrethroid ester insecticide.

: AC1O570W; NRDC-161; 52918-63-5; FMC-45498; ZINC01532093; RU 23938; UNII-26515THS0L component OWZREIFADZCYQD-BJLQDIEVSA-N

CAS : 52918-63-5
CAS Name: (1R,3R)-3-(2,2-Dibromoethenyl)-2,2-dimethylcyclopropanecarboxylic acid (S)-cyano(3-phenoxyphenyl)methyl ester
Additional Names: (S)-a-cyano-3-phenoxybenzyl-(1R)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane carboxylate; decamethrin; esbecythrin
Manufacturers’ Codes: FMC-45498; NRDC-161; RU-22974
Trademarks: Butox (Intervet); Decis (Bayer CropSci.); K-Othrine (Bayer CropSci.); Scalibor (Intervet)
Molecular Formula: C22H19Br2NO3
Molecular Weight: 505.20
Percent Composition: C 52.30%, H 3.79%, Br 31.63%, N 2.77%, O 9.50%
Properties: Crystals, mp 98-101°. Sol in ethanol, acetone, dioxane. Insol in water. LD50 in female rats (mg/kg): 31 orally; 4 i.v. (Kavlock).
Melting point: mp 98-101°
Toxicity data: LD50 in female rats (mg/kg): 31 orally; 4 i.v. (Kavlock)
Use: Insecticide.
Therap-Cat-Vet: Ectoparasiticide.
Malaria causes more than 300 million clinical cases and 665,000 deaths each year, and the majority of the mortality and morbidity occurs in sub-Saharan Africa. Due to the lack of effective vaccines and wide-spread resistance to antimalarial drugs, mosquito control is the primary method of malaria prevention and control. Currently, malaria vector control relies on the use of insecticides, primarily pyrethroids. The extensive use of insecticides has imposed strong selection pressures for resistance in the mosquito populations. Consequently, resistance to pyrethroids in Anopheles gambiae, the main malaria vector in sub-Saharan Africa, has become a major obstacle for malaria control. A key element of resistance management is the identification of resistance mechanisms and subsequent development of reliable resistance monitoring tools. Field-derived An. gambiae from Western Kenya were phenotyped as deltamethrin-resistant or -susceptible by the standard WHO tube test, and their expression profile compared by RNA-seq. Based on the current annotation of the An. gambiae genome, a total of 1,093 transcripts were detected as significantly differentially accumulated between deltamethrin-resistant and -susceptible mosquitoes. These transcripts are distributed over the entire genome, with a large number mapping in QTLs previously linked to pyrethorid resistance, and correspond to heat-shock proteins, metabolic and transport functions, signal transduction activities, cytoskeleton and others. The detected differences in transcript accumulation levels between resistant and susceptible mosquitoes reflect transcripts directly or indirectly correlated with pyrethroid resistance. RNA-seq data also were used to perform a de-novo Cufflinks assembly of the An. gambiae genome.

Purified deltamethrin is an off-white powder that has none to slight musty odour. Technical deltamethrin (purity 98.9-99.3%w/w) melts at 98.1-99.4 °C and decomposes before boiling (245-320 °C). The density is 1.5 g/cm3
at 20°C and the solubility in water is < 5µg/l at pH 6.2and 20 °C (based on the LOQ of the HPLC-method used for quantification). Deltamethrin is notconsidered to be able to dissociate within the environmentally relevant pH range due to the lack
of functional groups with acidic or alkaline properties. The vapour pressure is 1.24 x 10-8 Pa at
25 °C and the Henry’s law constant of 1.252 x 10-3 Pa.m3.mol-1 indicates that volatilisation is
not expected to significantly contribute to the dissipation of deltamethrin in the environment.
The Log Pow is 4.6 in distilled water (pH not stated) which indicates that deltamethrin may bioaccumulate. The following solvent solubilities were determined for deltamethrin (g/l): 300-600 (acetone), 60-75 (acetonitrile), >600 (1,2-dichloroethane), 200-300 (DMSO and ethyl actetate), 2.47 (n-heptane), 8.15 (methanol) and 150-200 (p-xylene). Deltamethrin is not highly
flammable, auto-flammable, exploosive or oxidizing and does not react with the packaging material (black plastic pouches).

Molecular formula:  C22H19Br2NO3

Chemical Structure

Chemical Structure

    Deltamethrin is the first pyrethroid composed of a single 
isomer of 8 stereoisomers selectively prepared by the 
esterification of [1R, 3R or  cis]-2,2-dimethyl-3-(2,2-dibromovinyl) 
cyclopropanecarboxylic acid with (alphaS)- or (+)-alpha-cyano-3-
phenoxybenzyl alcohol or by selective recrystallization of the 
racemic esters obtained by esterification of the (1R, 3R or  cis)-
acid with the racemic or [alphaR, alphaS, or alphaRS or ±]-alcohol 
(Elliott et al., 1974).  Thus, its stereospecific structure (4) is 
the ester of [1R, 3R or  cis]-acid with (alphaS)-alcohol. 

    The acid is a characteristic dibromo analogue of chrysanthemic 



Deltamethrin (S-α-cyano-3-phenoxybenzyl-(1R,3R)-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylic acid ester) is an insecticide from the class of the pyrethroids and has been used extensively and for a long time for controlling pests (C. D. S. Tomlin, The Pesticide Manual, 11th Edition, British Crop Protection Council, Farnham 1997).

Deltamethrin is a pyrethroid insecticide that kills insects on contact and through digestion. It is used to control apple and pear suckers, plum fruit moth, caterpillars on brassicas, pea moth, aphids (apples, plums, hops), winter moth (apples and plums), codling and tortrix moths (apples). Control of aphids, mealy bugs, scale insects, and whitefly on glasshouse cucumbers, tomatoes, peppers, potted plants, and ornamentals. It also controls numerous insect pests of field crops. Formulations include emulsifiable concentrates, wettable powders, ULV and flowable formulations and granules. There are no known incompatibilities with other common insecticides and fungicides

The pyrethroids with which the present invention is concerned are crystallizable esters having at least one asymmetric carbon atom to which an epimerizable proton is attached. The more pesticidally active pyrethroids additionally contain at least one and usually two or more other asymmetric carbon atoms and therefore comprise isomeric mixtures wherein one or more of the isomers are more pesticidally active than the others. Representative of such pyrethroids are the alpha-cyanobenzyl esters of the formula (A) :


Figure imgf000003_0001

wherein R1 is halogen, haloalkyl, alkenyl or halo- alkenyl; each R2 independently is halogen, alkyl, halo- alkyl, alkoxy, phenyl, phenoxy, phenylalkyl, substituted phenyl and substituted phenylalkyl wherein the substituents include one or more of alkyl, halogen, haloalkyl, nitro, hydroxy and cyano; and n is 0-5, preferably 1-3. In the above formula the asymmetric carbon atoms are marked 1, 3 and alpha. All of the substituents on a host group may be the same, or the substituents may be different. Alkyl and alkoxy may contain 1-8 carbon atoms, preferably 1-4 carbon atoms. Alkenyl may comprise 2-8 carbon atoms, preferably 2-4 carbon atoms. Halogen includes fluorine, chlorine and bromine. A typical phenylalkyl group is benzyl. Substituted phenyl includes tolyl, xylyl, trichlorophenyl and trifluoro- methylphenyl. Substituted phenylalkyl includes methyl- benzyl, trichlorobenzyl and trifluoromethylbenzyl.

The foregoing and other pyrethroids are well known as disclosed, for example, in Kirk-Othmer, Encyclopedia of Chemical Technology, Second Edition, Vol. 13, pages 456-458, in the following U.S. Patents: 4,024,163 – Elliot et al (NRDC)

4,133,826 – Warnant et al (Roussel Uclaf)

4,136,195 – Warnant et al (Roussel Uclaf)

4,213,916 – Davies et al (Shell)

4,287,208 – Fuchs et al (Bayer) 4,308,279 – Smeltz (FMC)

4,427,598 – Mason et al (Shell)

4,512,931 – Robson (ICI)

4,544,508 – Fuchs et al (Bayer)

4,544,510 – Van Berkel et al (Shell) 4,560,515 – Stoutamire et al (Shell)

4,582,646 – Stoutamire et al (Shell)

4,670,464 – Doyle et al (ICI)

4,681,969 – Williams et al (ICI) and in the following PCT patent publications:

WO 86/04215 – Hidasi et al (Chinoin)

WO 86/04216 – Hidasi et al (Chinoin)

Preferred pyrethroids convertible to more active isomers in accordance with the present invention are those of formula A wherein R1 is dihalovinyl or tetrahalopropenyl, R2 is phenoxy, and n is l. The more preferred pyrethroids are those wherein n is 1, R1 is dihalovinyl or tetrahalopropenyl and R2 is phenoxy; and those wherein n is 2, R1 is dihalovinyl or tetrahalopropenyl and one R2 is fluorine and the other R2 is phenoxy. The latter preferred compounds are isomeric mixtures having the common name “cyfluthrin” when R1 is dichlorovinyl, n is 2 and one R2 is fluorine. When R1 is dichlorovinyl, n is 1 and R2 is phenoxy, the mixtures have the common name “cypermethrin.”

Cypermethrin contains four cis and four trans isomers designated I-VIII as follows:

cis isomers I. (S) (α-cyano)(3-phenoxyphenyl)methyl 1R, cis-3-

(2,2-dichloroethenyl)-2,2-dimethylcyclopropane- carboxylate (abbreviated 1R, cis S)

II. (R)(α-cyano)(3-phenoxyphenyl)methyl 1S, cis-3- (2,2-dichloroethyl)-2,2-dimethylcyclopropane- carboxylate (abbreviated 1S, cis R)

III. (S)(α-cyano)(3-phenoxyphenyl)methyl 1S, cis-3- (2,2-dichloroethenyl)-2,2-dimethylcyclopropane- carboxylate (abbreviated 1S, cis S)

IV. (R)(α-cyano)(3-phenoxyphenyl)methyl 1R, cis-3-

(2,2-dichloroethenyl)-2,2-dimethylcyclopropane- carboxylate (abbreviated 1R, cis R)

trans isomers V. The trans isomer of I (abbreviated 1R, trans S)

VI. The trans isomer of II (abbreviated 1S,trans R)

VII. The trans isomer of III (abbreviated 1S,trans S)

VIII. The trans isomer of IV (abbreviated 1R, trans R)

Cyfluthrin and other pyrethroids to which the invention is applicable comprise similar isomericmixtures.

It is known that the most insecticidally active isomers of the foregoing eight isomers are I and V, and that enantiomer pairs I/II (abbreviated cis-2) and V/VI (abbreviated trans-2) are more insecticidally active than the enantiomer pairs III/IV (abbreviated cis-1) and VII/VIII (abbreviated trans-1). It is extremely difficult and commercially impractical to separate the more active isomers such as I and V from the complex isomer mixtures produced in the usual pyrethroid synthesis. Accordingly, efforts to produce more pesticidally active pyrethroids have focused on techniques for converting less active isomers in the synthesis product mixtures to more active isomers, i.e., to enrich isomeric mixtures with respect to the more active isomers, thus avoiding complex resolution procedures and the loss represented by discard of less active isomers.

Nevertheless, even when the isomeric mixtures have been converted rather than resolved, the conversion procedures have not been commercially practical because of poor yields, usually due to production of undesired by-product, often comprising as many isomers as the desired product, and because of time-consuming multiple steps, high temperatures and/or the need to recover expensive reagents. In the case of cypermethrin the major by-product is (R,S)-2-oxo-1,2-bis(3-phenoxyphenyl) ethyl cis- and trans-3-(2,2-dichloroethenyl)-2,2- dimethylcyclopropanecarboxylate, an eight isomer mixture commonly called the “benzoin by-product.” Similar byproducts are encountered in the synthesis of other pyrethroids such as cyfluthrin. Representative of prior efforts to convert isomer mixtures to more active species are the procedures disclosed in U.S. Patents 4,213,916, 4,308,279, 4,544,510, 4,544,508, 4,512,931, 4,427,598, 4,670,646 and 4,681,969 and the two PCT patent publications cited above.


Deltamethrin products are among the most popular and widely used insecticides in the world[citation needed] and have become very popular with pest control operators and individuals in the United States.[1] This material is a member of one of the safest classes of pesticides: synthetic pyrethroids. This pesticide is highly toxic to aquatic life, particularly fish, and therefore must be used with extreme caution around water. Although generally considered safe to use around humans, it is still neurotoxic to humans. Deltamethrin is able to pass from a woman’s skin through her blood and into her breast milk.[2]

There are many uses for deltamethrin, ranging from agricultural uses to home pest control. Deltamethrin has been instrumental in preventing the spread of diseases carried by tick-infested prairie dogsrodents and other burrowing animals[citation needed]. It is helpful in eliminating and preventing a wide variety of household pests, especially spidersfleastickscarpenter antscarpenter bees,cockroaches and bed bugs. Deltamethrin is also one of the primary ingredients in ant chalk.


Deltamethrin is a pyrethroid composed of a single isomer of 8 stereoisomers selectively prepared by the esterification of (1R,3R)- orcis-2,2-dimethyl-3-(2,2-dibromovinyl)cyclopropanecarboxylic acid with (alpha,S)- or (+)-alpha-cyano-3-phenoxybenzyl alcohol or by selective recrystallization of the racemic esters obtained by esterification of the (1R,3R)- or cis-acid with the racemic or (alpha-R,alpha-S, or alpha-R/S)- or + or − alcohol.


Chemical structure for deltamethrin


Evolution of an industrial process: deltamethrin synthesis
Chemistry&Industry (London, United Kingdom) (1984), (6), 199-204



Very efficient enantioselective syntheses of (1R)--and -hemicaronaldehydes precursors of (1R)-trans chrysanthemic acid and its (1R)-cis dibromovinyl analogue starting from natural tartaric acid or D-mannitol are described. They are based on the reaction between isopropylidenetriphenylphosphorane or isopropylidenediphenylsulfurane and chiral γ-alkoxy-α,β-unsaturated esters. The general problem of the diastereoselective addition to such esters is discussed.



Isopropylidenediphenylsulfurane reacts with γ-alkoxy α,β-unsaturated esters and produces γ-alkoxy cyclopropane carboxylates. This reaction is almost stereospecific and takes place with very high asymmetric induction. The stereochemistry of the resulting cyclopropane derivative proved independent of the stereochemistry of the carbon-carbon double bond of the starting ester. This reaction has been successfully applied to the enantioselective synthesis of deltamethrin (the most biologically active insecticide) from natural tartaric acid.

(+)-4 α-Acetyl-2-carene (6), readily available from (+)-3-carene (5), was converted to (1R)--(+)-3-(2′,2′-dihalovinyl)-2, 2-dimethyl-cyclopropane-1-carboxylic acids (21) and (22) in eleven steps and in overall yields of 23% and 14%, respectively. Alternatively, (-)-5-keto-3-carene (23), an oxidation product of (+)-3-carene (5) was converted to (1R)--(-)-permethrin (1) in five steps and in an overall yield of 20%. in yet another flexible approach, (-)-(23) was converted to (1R)--(+)-(21) and (1R)--(+)-(22) in seven steps and in an overall yields of 33% and 23%, respectively. These results coupled with the literature reports for the conversion of (1R)--(+)-(21) and (22) to (1R)--(-)-(1), (1R)-cis-(+)-cypermethrin (2) and (1R)--(+)-deltamethrin (decis) (3) constitute two efficient methods for the synthesis of (1R)--synthetic pyrethroid from (+)-3-carene (5).


1R-cis-2,2-Dimethyl-3-(2,2-dibromovinyl)cyclopropane carboxylic acid1 (1), the acid moiety of the highly potent photostable pyrethroid deltamethrin (2) has been obtained either by a Wittig reaction on 1R-cis-caronaldehyde ester (3) employing 1, 1-dibromomethylenetriphenylphosphorane or from the bicyclic tribromo-lactone2,3 (4) by reaction with zinc and acetic acid. Lactone (4) is thus an important intermediate in the deltamethrin synthesis.



Physical and Chemical Properties

    Technical grade deltamethrin contains more than 98% deltamethrin
(FAO/WHO, 1981).  It is stable to heat (6 months at 40 °C), light,
and air, but unstable in alkaline media (FAO/WHO, 1981; Meister et
al., 1983; Worthing & Walker, 1983).  Some physical and chemical
properties are listed in Table 1, and the chemical composition of
various stereoisomeric mixtures is shown in Table 2. 

Table 1.  Some physical and chemical properties of deltamethrin
Physical state            crystalline powder 
Colour                    colourless
Odour                     odourless
Density (20 °C)           0.5 g/cm3
Relative molecular mass   505.24
Melting point (°C)        98-101
Boiling point             decomposes above 300 °C
Water solubility (20 °C)  < 0.002 mg/litre (practically insoluble)
Solubility in organic     solublea
Vapour pressure (25 °C)   2.0 x 10-6 Pa
 n-Octanol-water           5.43
 partition coefficient 
 (Log Pow) 
a Acetone (500 g/litre), ethanol (15 g/litre), cyclohexanone (750 
  g/litre), dioxane (900 g/litre), xylene (250 g/litre), ethyl 

2.3  Analytical Methods

    Methods for the determination of deltamethrin residues and the 
analysis of environmental samples, and products are summarized in 
Table 3. 

    To analyse technical grade deltamethrin, a mixture of 
deltamethrin and diphenylamine (an internal standard) was injected 
in a high-performance liquid chromatograph equipped with a UV-
detector (Mourot et al., 1979). 

    The Joint FAO/WHO Codex Alimentarius Commission has published 
recommendations for methods for the determination of deltamethrin 
residues (FAO/WHO 1985b).  A further review of analytical methods 
for deltamethrin has been made by Vaysse et al. (1984). 

Table 2.  Chemical identity of deltamethrins of various stereoisomeric compositions
Common name           CA Index name (9CI)                        Stereoisomeric  Synonyms and trade names
CAS Registry No.                                                 compositionc    
NIOSH Accession No.a  Stereospecific nameb
Deltamethrin          Cyclopropanecarboxylic acid,               (4)             Decamethrin, Decis,
52918-63-5            3-(2,2-dibromovinyl)-2,2-dimethyl-,                        K-Othrine, NRDC 161,
GZ1233000a            alpha-cyano(3-phenoxyphenyl)methyl ester,                  WHO 1998, K-Obiol, Butox
                      [1R-[1 (S*), 3 R]]-,                                       Butoflin, Cislin, FMC 45498
                                                                                 RU 22974

                      (1R,  cis)-2,2-dimethyl-3-(2,2-di-

d- cis-Deltamethrin    same as deltamethrin                       -               Decamethrin, Decis
GZ1240000a            (S)-alpha-cyano-3-phenoxybenzyl
                      (d,  cis)-2,2-dimethyl-3-(2,2-di-
a Registry of Toxic Effects of Chemical Substances (RTECS) (1981-82 edition).
b (1R), d, (+) or (1S), 1, (-) in the acid part of deltamethrin signifies the same stereospecific conformation, 
c The number in the parenthesis identifies the structure shown in the figures of stereoisomers.

Table 3.  Analytical methods for deltamethrin
Sample         Extraction    Sample preparation                     Determination:         MDCb     % Recovery          Reference
               solvent       -----------------------------------                           (mg/kg)  (fortification
                             Partition     Clean up                 GLC or HPLC                     level in
                                           column      elution      condition; detector,            mg/kg)  
                                                                    carrier flow, column,
                                                                    temp, R.T.a

apple           n-hexane/     ext.sol.c/    silica gel  CH2Cl2       ECD-GC; N2;            0.01     105(0.1), 100(1.0)  1
               acetone       H2O                                    50 ml/min; 1 m 
               (1/1)                                                3% OV-7; 235 °C
pear                                                                                       0.01     125(0.1), 98(1.0)   
cabbage                                                                                    0.01     130(0.1), 118(1.0) 
potato                                                                                     0.01     126(0.1), 97(1.0) 

apple,         acetonitrile  petroleum     Florisil    ether/       EDC-GC; 1.2 m          0.005    85-100(0.02-0.1)    2 
peach,                       ether/H2O                  n-hexane     DC-200, OV-1 or 
grape,                                                 (1/4)        OV-101; 245 °C,  
tomato                                                              10-12 min

wheat          methanol       n-hexane      alumina                  HPLC; 235 nm;                   87(2.0)             3
grain                                                               30 cm; uBondapak;
                                                                    C 18; methanol/H2O
                                                                    (4/1); 2.5 ml/min

wheat                         n-hexane      Florisil    ether/       ECD-GC; N2;                     91                  4
                                                       petroleum    75 ml/min; 0.6 m 
                                                       ether (1/9)  5% SE-30; 215 °C

meat           ethyl ether/  acetonitrile  gel         diisopropyl  ECD-GLC; N2;           0.001    90-95% at 0.01      5
               petroleum                   permeation  ether        40 ml/min; 1.8 m
               ether                       column                   SE-30 1% on gas 
                                           (Styragel)               Chrom. PAW

milk           hexane        acetonitrile  Florisil +  benzene/     ECD-GLC; N2;           0.01     83-87% at 0.1       5
                                           cellulose/  hexane       40 ml/min; 1.8 m  
                                           charcoal    (1/1)        SE-30 1% on gas
                                                                    Chrom. PAW 

Table 3.  (contd.)
Sample         Extraction    Sample preparation                     Determination:           MDCb     % Recovery          Reference
               solvent       -----------------------------------                             (mg/kg)  (fortification
                             Partition     Clean up                 GLC or HPLC                       level in
                                           column      elution      condition; detector,              mg/kg)  
                                                                    carrier flow, column,
                                                                    temp, R.T.a

locust          n-hexane                    Florisil    ether/       ECD-GC; N2;                       92                  4
                                                       petroleum    75 ml/min; 0.6 m 5%
                                                       ether (1/9)  SE-30; 215 °C 

sea water      XAD-2         ext.sol.c/    alumina                  ECD-GC; N2;                                           6
               resin          n-hexane                               70 ml/min; 1.5 m 
               acetone                                              4% SE-30; 207 °C

water           n-hexane                    alumina                  ECD-GC; N2;                                           6
                                                                    70 ml/min; 1.5 m 
                                                                    4% SE-30; 207 °C 

water          petroleum                   Florisil    petroleum    ECD-GLC; 1 m OV          0.0001   97 at 0.010         8
               ether/                                  ether/       1-3% on Chromosorb
               diethyl-                                diethyl-     W.A.W. HMDS 60/80
               ether (1/1)                             ether   

soil           acetone,                    acid        hexane       ECD-GLC; 5.2%            0.001    > 91%               9
               acetone/                    alumina     ether        OV-210 with AR/CH4
               hexane (1/1)                            hexane 
               hexane                                  (5-10%)

               acetone,                    acid        hexane/      ECD-GLC; N2;             0.0001   > 91%               5
               acetone/                    alumina     ethyl ether  40 ml/min; 1.8 m 
               hexane (1/1)                            (90/10)      SE-30 1% on gas 
               hexane                                               Chrom. PAW

cotton          n-hexane                                             transesterification                                   7
foliage                                                             followed by ECD-GC; 
(dislodgeable                                                       31 ml/min; 0.45 m    
residue)                                                            5% SE-30; 120 °C

Table 3.  (contd.)
Sample         Extraction    Sample preparation                     Determination:           MDCb     % Recovery          Reference
               solvent       -----------------------------------                             (mg/kg)  (fortification
                             Partition     Clean up                 GLC or HPLC                       level in
                                           column      elution      condition; detector,              mg/kg)  
                                                                    carrier flow, column,
                                                                    temp, R.T.a

Technical                                                           HPLC, 230 nm; 15 cm                                   10
grade                                                               Lichrosorb Si-60; 
                                                                    ether (93/7); 80 ml/h; 
                                                                    7.6 min    

               isoctane/                                            HPLC - UV detector                                    5
               dioxane                                              254 nm (230 nm for
               (80/20)                                              conc. <0.5%) Silica-60; 
                                                                    100ml/h; isooctane/ 
                                                                    dioxane (95/5)   
a R.T.:  retention time;
b MDC: minimum detectable concentration;
c ext .sol.: extraction solvent.


1. Baker & Bottomley (1982); 2. Mestres et al. (1978a); 3. Noble et al. (1982); 4. Pansu et al. (1981); 5. Vaysse et al. (1984); 
6. Zitko et al. (1979); 7. Estesen et al. (1979); 8. Mestres et al. (1978b); 9. Hill (1982); 10. Mourot et al. (1979). 

3.1  Industrial Production

    Deltamethrin was first marketed in 1977.  Production volumes in 
recent years are shown in Table 4. 

Table 4.  Worldwide production of deltamethrin
Year  Production  Reference
1979  75          Wood Mackenzie (1980)
1980  100         Wood Mackenzie (1981)
1981  100         Wood Mackenzie (1982, 1983)
1982  115         Wood Mackenzie (1983)
1987  250         Information from Roussel Uclaf


Malaria control

Deltamethrin plays key role in controlling malaria vectors, and is used in the manufacture of long-lasting insecticidal mosquito nets. It is used as one of a battery of pyrethroid insecticides in control of malarial vectors, particularly Anopheles gambiae, and whilst being the most employed pyrethroid insecticide, can be used in conjunction with, or as an alternative to, permethrincypermethrin and other organophosphate-based insecticides, such as malathion and fenthion. Resistance to deltamethrin (and its counterparts) is now extremely widespread and threatens the success of worldwide vector control programmes.

Resistance to deltamethrin

Resistance has been characterised in several insects, including important vectors of malaria like the mosquito Anopheles gambiae as well as non-disease carrying pests like bed bugs.


Methods of resistance include thickening of the cuticle of the insect to limit permeation of the insecticide, metabolic resistance via overexpression of metabolising P450 mono-oxygenases and glutathione-S-transferases, and the knockdown resistance (kdr) sodium channel mutations which render the action of insecticides ineffectual, even when co-administered with piperonyl butoxide. Characterisation of the different forms of resistance among mosquitoes has become a top priority in groups studying tropical medicine due to the high mortality of those who reside in endemic areas.[3]

Bed Bugs

Two mutations, the Valine to Leucine mutation (V419L) and the Leucine to Isoleucine mutation (L925I) in voltage-gated sodium channel α-subunit gene, have been identified as responsible for knockdown resistance to deltamethrin in bed bugs. One study found that 88% of bed bug populations in the US had one, the other, or both mutations, meaning that deltamethrin resistance among bed bugs is currently making this insecticide obsolete.[4]


In humans

Since deltamethrin is a neurotoxin, it temporarily attacks (in medical terms, “insults”) the nervous system of any animal with which it comes into contact. Skin contact can lead to tingling or reddening of the skin local to the application. If taken in through the eyes or mouth, a common symptom is facial paraesthesia, which can feel like many different abnormal sensations, including burning, partial numbness, “pins and needles”, skin crawling, etc. There are no reports indicating that chronic intoxication from pyrethroid insecticides causes motor neuron damage or motor neuron disease.[5] However, in 2011, a case report was published that demonstrated pathologically proven motor-neuron death in a Japanese woman after acute massive ingestion of pesticides containing pyrethroids and organochlorine. [6]

Recently, in South Africa, residues of deltamethrin were found in breast milk, together with DDT, in an area that used DDT treatment for malaria control, as well as pyrethroids in small-scale agriculture.[7]

There are no antidotes, and treatment must be symptomatic, as approved by a physician. Over time, deltamethrin is metabolized, with a rapid loss of toxicity, and passed from the body. A poison control center should be contacted in the event of an accidental poisoning.

In domestic animals

Cases of toxicity have been observed in cattle, following use of agricultural deltamethrin preparation in external application in tick control. Symptoms appeared 36 hours after the application, and included muscular tremors that lead to decubitus 12 hours later. After 12 hours, there was spontaneous recovery and the animal could stand up again, although the muscular tremors persisted. The body temperature was then 38.3°C. (normal range 38.0 to 39.5°C.).


CAS number 52918-63-5 Yes
ChemSpider 37079 Yes
KEGG D07785 Yes
ChEBI CHEBI:4388 Yes
ATC code P03BA03,QP53AC11
Jmol-3D images Image 1
Molecular formula C22H19Br2NO3
Molar mass 505.20 g mol−1
Density 1.5 g cm−3
Melting point 98 °C (208 °F; 371 K)
Boiling point 300 °C (572 °F; 573 K)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)




  1.  “Deltamethrin Odorless Synthetic Pyrethroid Insecticides”. PestProducts.com. Retrieved 2008-09-26.
  2. Bouwman, B. Sereda and H.M. Meinhardt, H.; B. Sereda and H.M. Meinhardt (December 2006). “Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa”Environmental Pollution 144 (3): 902–917. doi:10.1016/j.envpol.2006.02.002PMID 16564119. Retrieved 2008-09-26.
  3. Muller, Pie, et al. (2008). Field caught Permethrin-Resistant Anopheles gambiae overexpress CYP6P3, a P450 that metabolises pyrethroids,PLoS Genetics 4(11)).
  4.  Zhu, F.; Wigginton, J.; Romero, A.; Moore, A.; Ferguson, K.; Palli, R.; Potter, M. F.; Haynes, K. F.; Palli, S. R. (2010). “Widespread distribution of knockdown resistance mutations in the bed bug,Cimex lectularius(Hemiptera: Cimicidae), populations in the United States”. Archives of Insect Biochemistry and Physiology: n/a. doi:10.1002/arch.20355.
  5.  Doi, et al (2006). “Motor neuron disorder simulating ALS induced by chronic inhalation of pyrethroid insecticides”. Neurology 67 (10). pp. 1894–1895.doi:10.1212/01.wnl.0000244489.65670.9f.
  6.  Doi, et al (2006). “Motor neuron disorder simulating ALS induced by chronic inhalation of pyrethroid insecticides”. Neurology 67 (10). pp. 1894–1895.doi:10.1212/01.wnl.0000244489.65670.9f.
  7.  Bouwman, B. Sereda and H.M. Meinhardt, H.; B. Sereda and H.M. Meinhardt (December 2006). “Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa”Environmental Pollution 144 (3): 902–917. doi:10.1016/j.envpol.2006.02.002PMID 16564119. Retrieved 2008-09-26.

External links


Literature References:

Synthetic pyrethroid insecticide. Prepn of racemic mixture: M. Elliot et al., DE 2439177 (1975 to NRDC),C.A. 83, 73519z (1975); of decamethrin and isomers: eidem,

Pestic. Sci. 9, 105 (1978). Activity: eidem, Nature 248, 710 (1974);eidem, Pestic. Sci. 9, 112 (1978).

Absolute configuration: J. D. Owen, J. Chem. Soc. Perkin Trans. 1 1975, 1865.

Photochemistry: L. O. Ruzo et al., J. Agric. Food Chem. 25, 1385 (1977).

Metabolism: eidem, ibid. 26, 918 (1978). Toxicology: R. Kavlock et al., J. Environ. Pathol. Toxicol. 2, 751 (1979).

Pharmacological effects on central nervous system: P. H. Chanh et al.,Arzneim.-Forsch. 34, 175 (1984).

Review of toxicology and human exposure: Toxicological Profile for Pyrethrins and Pyrethroids(PB2004-100004, 2003) 332 pp.



1. Elliott, M., Farnham, A. W., Janes, N. F., Needham, P. H., and Pulman, D. A., Nature, 244, 456 (1973).
2. Elliott, M., Farnham, A. W., Janes, N. F., Needham, P. H., Pulman, D. A., and Stevenson, J. H., Nature, 246, 169 (1973).
3. Elliott, M., Farnham, A. W., Janes, N. F., Needham, P. H., Pulman, D. A., and Stevenson, J. H., Proc. Seventh Br. Ins. Fung. Conf. (Brighton) 721 (1973).
4. Cahn, R. S., Ingold, C., and Prelog, V., Angew. Chem. int. Ed. Engl., 5, 385 (1966).
5. Brown, D. G., Bodenstein, O. F., and Norton, S. J., J. agric. Fd Chem., 21, 767 (1973).
6. Lock, G., and Kempter, F. H., Ml Chem., 67, 24 (1935).
7. Elliott, M., Farnham, A. W., Janes, N. F., Needham, P. H., and Pearson, B. C., Nature, 213, 493 (1967).
8. Elliott, M., Chem. and Ind., 776 (1969).
9. Elliott, M., Bull. Wld Hlth Org., 44, 315 (1971).
10. Becker, W., and Pfeifl, E., J. Am. chem. Soc., 88, 4299 (1966).
11. Chemistry of Carbon Compounds (edit. by Rodd, E. H.) III, 902 (Elsevier, 1956).
12. Barnes, J. M., and Verschoyle, R. D., Nature, 248, 711 (1974).


Stabilized mixtures of carbamate insecticides and synthetic pyrethroids
Stabilized mixtures of carbamate insecticides and synthetic pyrethroids. STABILIZED MIXTURES OF CARBAMATE INSECTICIDES AND SYNTHETIC PYRETHROIDS
Stabilized cyandhydrin ester
Conversion of stereoisomer into its diastereoisomer
Oct 252014



The continuous flow synthesis of carboxylic acids using CO2 in a tube-in-tube gas permeable membrane reactor

A. Polyzos, M. O’Brien, T. Pugaard-Petersen, I.R. Baxendale, S.V. Ley, Angew. Chem. Int. Ed. 2011, 50, 1190-1193.



Keep it simple: A gas–liquid flow reactor has been developed based on a gas permeable tube-in-tube configuration which effectively delivers gas to a liquid substrate stream in a safe, continuous fashion. A series of carboxylic acids were prepared from the reaction of CO2with a range of Grignard reagents (see picture).

The gas-liquid reactor assembly is comprised of a 1 m section of Teflon AF-
2400 tubing (0.8 mm o.d.; 0.6 mm i.d.) placed within PTFE tubing (3.2 mm o.d.; 1.6
mm i.d). These tubings were coiled and each end fastened to a 1/8” stainless steel tube
fitting, which was fixed onto an aluminium base plate. One section of the Teflon AF-
2400 membrane tubing was passed through to a stainless steel T-piece (Swagelok 2 ×
1/8”, 1 × 16” fittings) that was united with PTFE tubing (1/16”), forming the liquid
inlet. The other section of the Teflon AF-2400 was passed through a 4-way stainless
steel connector (Swagelok, 3 × 1/8”, 1 × 16” fittings) and directly united with a
second piece of PTFE tubing (1/16”), forming the liquid outlet. One of the 1/8”
fittings on the 4-way connector was attached to a fine needle release valve (Swagelok)
used to purge the reactor of excess gas. The remaining connector was attached to
another stainless steel T-piece (Swagelok 3 × 1/8” fittings) that was connected to a
pressure gauge (Swagelok, 10 Bar) and a gas pressure regulator valve (10 bar
maximum) via stainless steel tubing (1/8”) (Figure S1).

Inline image 1

Inline image 2


Two flow streams driven by the Vapourtec R4/R2+; stream 1 containing a
solution of 1a (1.0 M in THF, 1.0 equiv, 1.0 mmol) loaded into a 2mL PEEK loop
and stream 2 containing the dry THF, were mixed at a T-piece before entering the
gas-liquid tube-in-tube reactor at room temperature. A back pressure regulator (75
psi) was placed immediately after the gas-liquid reactor to prevent out-gassing of the
dissolved CO2 from the solvent stream in the reactor. The flow stream was collected
in a flask containing a biphasic mixture of saturated ammonium chloride solution and
diethyl ether (1:1) (20 mL). The solution was acidified with HCl (1.0 M) and the
product was extracted with EtOAc (2 × 10 mL), dried (Na2SO4) and solvent removed
in vacuo to give the crude product 1b.


Oct 182014




MW 101

the degree of unsaturation: the answer is 0. The molecule has no double bonds or rings.



IR Spectrum

Since the molecule has a nitrogen, look for a band in the region 3400-3250 – there is a single small band at 3384, which probably indicates the N-H stretch of a secondary amine. (Recall that tertiary amines will not show a band in this region because they do not have any N-H’s to stretch.)




NMR Spectrum





Amine protons show up from 0.5-3.0 ppm if the amine is not on an aromatic ring; the small “buried” peak at 1 ppm indicates a secondary amine peak:

There are only two other types of protons in the molecule: the doublet at 1 ppm indicates 12 hydrogens adjacent to one hydrogen and the septet at 2.9 ppm indicates 2 hydrogens adjacent to 6 hydrogens. The only way the molecule can be “put together” is to have each R group coming off the nitrogen to be the same, and to be -CH(CH3)2.





Example is diisopropylamine:

Oct 172014
Chemical structure of prismane

650-42-0 cas


Prismane is a polycyclic hydrocarbon with the formula C6H6. It is an isomer of benzene, specifically a valence isomer. Prismane is far less stable than benzene. The carbon (and hydrogen) atoms of the prismane molecule are arranged in the shape of a six-atomtriangular prismAlbert Ladenburg proposed this structure for the compound now known as benzene.[1] The compound was not synthesized until 1973.[2]
Chemical structure of prismane Chemical structure of prismane
CPK model of prismane
CAS number 650-42-0 
ChemSpider 16736515 Yes
Jmol-3D images Image 1
Molecular formula C6H6
Molar mass 78.11 g mol−1


In the mid 19th century, investigators proposed several possible structures for benzene which were consistent with its empirical formula, C6H6, which had been determined by combustion analysis. The first, which was proposed by Kekulé in 1867, later proved to be closest to the true structure of benzene. This structure inspired several others to propose structures that were consistent with benzene’s empirical formula; for example, Ladenburg proposed prismane, Dewar proposed Dewar benzene, and Koerner and Claus proposedClaus’ benzene. Some of these structures would be synthesized in the following years. Prismane, like the other proposed structures for benzene, is still often cited in the literature, because it is part of the historical struggle toward understanding the mesomeric structures and resonance of benzene. Some computational chemists still research the differences between the possible isomers of C6H6.[3]


Prismane is a colourless liquid at room temperature. The deviation of the carbon-carbon bond angle from 109° to 60° in a triangle leads to a high ring strain, reminiscent of that of cyclopropane but greater. The compound is explosive, which is unusual for a hydrocarbon. Due to this ring strain, the bonds have a low bond energy and break at a low activation energy, which makes synthesis of the molecule difficult; Woodward and Hoffmann noted that prismane’s thermal rearrangement to benzene is symmetry-forbidden, comparing it to “an angry tiger unable to break out of a paper cage.”[4]

The substituted derivative hexamethylprismane (in which all six hydrogens are substituted by methyl groups) has a higher stability, and was synthesized by rearrangement reactionsin 1966.[5]


Synthesis of Prismane

The synthesis starts from benzvalene (1) and 4-phenyltriazolidone, which is a strong dienophile. The reaction is a stepwise Diels-Alder like reaction, forming a carbocation as intermediate. The adduct (2) is then hydrolyzed under basic conditions and afterwards transformed into a copper(II) chloride derivative with acidic copper(II) chloride. Neutralized with a strong base, the azo compound (3) could be crystallized with 65% yield. The last step is a photolysis of the azo compound. This photolysis leads to a biradical which forms prismane (4) and nitrogen with a yield of less than 10%. The compound was isolated by preparative gas chromatography.


Chemical structure
MeLi, CH2Cl2, 
-45 °C, 45 %
Chemical structure


Chemical structure

Et2O, Dioxane
0 °C to RT, 60 min, 50-60 %

Chemical structure
Reflux, 24 h
Chemical structure
CuCl2, HCl,
65 % (2 steps)
Chemical structure
30 °C, 5 h, 8 %
Chemical structure








  1. Ladenburg A. (1869). “Bemerkungen zur aromatischen Theorie“. Chemische Berichte 2: 140–2. doi:10.1002/cber.18690020171.
  2. Katz T. J., Acton N. (1973). “Synthesis of Prismane”. Journal of the American Chemical Society 95 (8): 2738–2739. doi:10.1021/ja00789a084.
  3.  UD Priyakumar, TC Dinadayalane, GN Sastry (2002). “A computational study of the valence isomers of benzene and their group V hetero analogs”New J. Chem. 26 (3): 347–353.doi:10.1039/b109067d.
  4. R. B. Woodward and R. Hoffmann, Angew. Chem., Int. Ed. Engl.8, 789, (1969)
  5.  Lemal D. M., Lokensgard J. P. (1966). “Hexamethylprismane”. Journal of the American Chemical Society 88 (24): pp 5934–5935. doi:10.1021/ja00976a046.
Oct 092014


Highly potent APIs: can lean manufacturing ever be safe?

By Fiona Barry +, 09-Oct-2014

The phrase “lean manufacturing” conjures up job cuts and not much more for many people, but managers can use the method to drastically simplify HPAPI (highly potent active pharmaceutical ingredients) production, says an expert.


Oct 092014



Green chemistry makes ‘cents’ for cost-focused API firms says expert

By Gareth MacDonald+, 07-Oct-2014

Making drugs generates a huge amount of waste but industry is showing signs of cleaning up its act according to Paul Anastas, the Yale scientist who coined the phrase “green chemistry.”


Oct 082014
Dr. Rafael "Rafi" Boritzer


Global Biotech Marketer, Serial Entrepreneur, Academician, Chair of Bioinfomedical Ltd. (www.bioinfomedical.com)
WE SALUTE YOU, SIR ……for your enormous contribution to society


His public appeal in his own words
Aloha Bio Research-Education Friends and Colleagues,I appreciate your recent linking to me on the LinkedIn network and directly at boritzer@bioinfomedical.com Our Mission is to provide molecular biological product support, for research and development of Biosimilars, Personalized Medicine, and Traditional Pharma.Through our networks and relationships in over 60 countries, we help engage the scientific community in the cure and treatment of life-threatening and newly emerging diseases. You can find us at www.bioinfomedical.com , where our enterprise guarantees the highest levels of purity at “budget-constrained” prices. If you prefer to “buy the machine” instead of the product, we do offer the technology to produce any of our over 3,500 recombinant proteins and antibodies. If you do not find what you need in our online catalog (bottom right of landing page), we will be happy to entertain custom orders.With our accumulated experience in graduate and distance learning, we actively encourage, participate, and support American biotechnology and biological sciences education (Certificate, Masters, and Ph.D.). Our hybrid formats integrate short campus residency at first rate “bricks and mortar” campuses, on-line synchronous and asynchronous instruction, and the use of strategically located research labs in the U.S.A., Europe, and Asia.We look forward to meeting your needs.Thank you,
Dr. Rafi

Dr. Rafael "Rafi" Boritzer

Dr. Rafael “Rafi” Boritzer

Global Biotech Marketer, Serial Entrepreneur, Academician, Chair of Bioinfomedical Ltd.

  1. ThinkTech Hawaii,
  2. Bioinfomedical Ltd. / InfoMedical L.L.C.http://www.linkedin.com/in/doctorboritzer


Chairman of the Board of Directors

Bioinfomedical Ltd. / InfoMedical L.L.C. 

Started and built entrepreneurial venture that began as a consulting firm and grew into a successful business engaged in the global transfer of medical/gerontological technologies and software, marketing of research cytokines, and strategic alliances with bio-similar producers. Fostered relationships in Hawaii, Central/Southeast Asia, Oceania, Central Europe, Middle East, and East Africa, to accelerate growth of the business and further its objectives. Created differentiation strategies designed to cope with competitive marketing pressures primarily in long-term healthcare, specialty medical institutions and pharmaceutical distributors in the U.S. and Southeast Asia.


Dr. Rafi on Sociology at the University of Hawaii

Dr. Rafi on Sociology at the University of Hawaii




Over the course of my 20+ year career as an interdisciplinary and multicultural university educator, social scientist, marketer, entrepreneur and administrator, I have directed organizations, programs and initiatives that promote academic excellence, improve student performance, and strengthen educational outcomes. I have taught at Professor levels in the disciplines of healthcare administration, healthcare management information systems, sociology, global marketing and more. I have a track record in leading and participating in accreditation requirements, and in driving the design and development of curriculum and course offerings, at both graduate and undergraduate levels. My international experience encompasses five continents and I have an in-depth understanding of geopolitical contexts of business and effects on global and local economy and education.

Complementing my teaching and administrative background is executive and research experience in healthcare, geriatrics, entrepreneurship, and marketing, including the conceptualization, startup, and growth of a successful firm engaged in the global transfer of medical/gerontological technologies and software, marketing of research cytokines, and strategic alliances. InfoMedical Biotechnology (www.bioinfomedical.com) satisfies customers’ demand for high quality cytokine products. The use of medical diagnostics is growing in importance, as bigger proportion of the world’s population age and the cost of healthcare continues to rise. The company provides scientists with tools to investigate the genetic and molecular basis for human development and disease; knowledge that is applied in development, discovery and manufacture of new drugs.

Specialties: Education Program Development; Teaching; Student Recruitment-Retention; Distance Learning Modalities; Research & funding; Community Health; Sustainable Entrepreneurship; Strategic Planning; Sociology; Disruptive Innovation; and Global Business Strategies.

Senior project presentations at University of Hawaii Entrepreneurship Baccalaureate

Senior project presentations at University of Hawaii Entrepreneurship Baccalaureate

Live Life Aloha Obesity Reduction

Live Life Aloha Obesity Reduction


More about him

TV Talk Show Host

ThinkTech Hawaii

 – Present (10 months)Honolulu, HawaiiDr. Rafi conducts the weekly broadcast of Boritzer’s Bio Briefings. The hourly show focuses on the Biotechnological, Health and Medical sectors that are changing the way we live, eat, work, and socialize in the 21st Century. www.thinktechhawaii.com (live streaming on Mondays @ 15:00 Hawaiian Standard Time). Available after 24 hours (http://tinyurl.com/lnulduz).

From New York to Singapore, "Hospitals I've Learned to Love" with Dr. Rafi Boritzer

From New York to Singapore, “Hospitals I’ve Learned to Love” with Dr. Rafi Boritzer

Dr. Rafi Reveals IUI, IVF & Transactions at the Sperm Bank

Dr. Rafi Reveals IUI, IVF & Transactions at the Sperm Bank

Live, Life with Aloha - Obesity Reduction MadeEasy- Dr. Rafi Boritzer

Live, Life with Aloha – Obesity Reduction MadeEasy- Dr. Rafi Boritzer

The Health Care Highway -From Kolkata to Kapolei with Dr. Rafael Boritzer

The Health Care Highway -From Kolkata to Kapolei with Dr. Rafael Boritzer

Tele Medicine Systems - Dr. Rafi Boritzer with Dr. Dan Davis

Tele Medicine Systems – Dr. Rafi Boritzer with Dr. Dan Davis

In Telomere Research, SIZE is Everything-Dr. Rafi and Prof. Richard Allsopp

In Telomere Research, SIZE is Everything-Dr. Rafi and Prof. Richard Allsopp

If You Are A Baby Boomer, The Future is Now

If You Are A Baby Boomer, The Future is Now

Dr. Rafi chats with Prof. Tom Huang, Lab Director @ Pacific InVitro Fertilization

Dr. Rafi chats with Prof. Tom Huang, Lab Director @ Pacific InVitro Fertilization

Dr. Rafi and Prof. Clair Wright discuss "Pregnancy Dangers and Outcomes"

Dr. Rafi and Prof. Clair Wright discuss “Pregnancy Dangers and Outcomes”

Islands of Health- Dr Rafi on Fiji, Timor-Leste, Singapore, Madagascar, and Sicily

Islands of Health- Dr Rafi on Fiji, Timor-Leste, Singapore, Madagascar, and Sicily

Dr. Rafi Chases Ambulances from Honolulu to Tahrir Square

Dr. Rafi Chases Ambulances from Honolulu to Tahrir Square

Who is following you when you check into a long term care facility - Boritzer's Bio Briefings

Who is following you when you check into a long term care facility – Boritzer’s Bio Briefings

Cuban Healthcare: Can you achieve more with less?

Cuban Healthcare: Can you achieve more with less?




Canoe Blessing 1 of 2

Canoe Blessing 1 of 2

Canoe Blessing 2 of 2

Canoe Blessing 2 of 2

Dr. Rafi on Globalization at University of Hawaii

Dr. Rafi on Globalization at University of Hawaii

Dr. Rafi on Entrepreneurship at the University of Hawaii

Dr. Rafi on Entrepreneurship at the University of Hawaii

  1. Advice for Contacting Dr. Rafael “Rafi”

    As as an academic and consultant, I am available for year round consulting projects and visiting professor assignments. Contact: boritzer@bioinfomedical.com , LinkedIn messages, Facebook messages.

This was my tribute to a great living legend


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