AUTHOR OF THIS BLOG

DR ANTHONY MELVIN CRASTO, WORLDDRUGTRACKER
Apr 222017
 

Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile

 Green Chem., 2017, Advance Article
DOI: 10.1039/C7GC00602K, Communication
Katharina J. Hock, Robin Spitzner, Rene M. Koenigs
Applications of diazo acetonitrile in cyclopropa(e)nation reactions are realized in a slow-release protocol with bench-stable reagents. Cyclopropyl nitriles are obtained in one step in good diastereoselectivity on a gram-scale providing an efficient entry into this class of fragrances and drug-like molecules.
STR1
STR2
trans-2-phenylcyclopropane-1-carbonitrile
colorless solid (46 mg, 81%);
m.p. = 29°C;
1 H-NMR (600 MHz, CDCl3): δ = 7.34 – 7.30 (m, 2H), 7.28 – 7.24 (m, 1H), 7.12 – 7.08 (m, 2H), 2.63 (ddd, J = 9.2, 6.7, 4.7 Hz, 1H), 1.62 (dt, J = 9.2, 5.4 Hz, 1H), 1.55 (ddd, J = 8.7, 5.5, 4.8 Hz, 1H), 1.45 (ddd, J = 8.8, 6.7, 5.3 Hz, 1H);
13C-NMR (151 MHz, CDCl3): δ = 137.55, 128.76, 127.41, 126.31, 121.05, 24.90, 15.24, 6.63;
HRMS (ESI): m/z calc. for [C10H9NNa]: 166.06272, found 166.06276;
IR (KBr): νmax/cm-1 = 3044, 2235, 2098, 1761, 1600, 1461, 1220, 1051, 920, 705.
The analytical data is in correspondence with the literature [2]
STR1 STR2
[2] M. Gao, N. N. Patwardhan, P. R. Carlier, J. Am. Chem. Soc., 2013, 135 (38), 14390–14400

Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile

Author affiliations

Abstract

Diazo acetonitrile has long been neglected despite its high value in organic synthesis due to a high risk of explosions. Herein, we report our efforts towards the transient and safe generation of this diazo compound, its applications in iron catalyzed cyclopropanation and cyclopropenation reactions and the gram-scale synthesis of cyclopropyl nitriles.

Graphical abstract: Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile
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(3R)-4-[2-chloro-6-[[(R)-methylsulfinyl]methyl]pyrimidin-4-yl]-3-methyl-morpholine

 spectroscopy  Comments Off on (3R)-4-[2-chloro-6-[[(R)-methylsulfinyl]methyl]pyrimidin-4-yl]-3-methyl-morpholine
Feb 092017
 

STR1

 

(3R)-4-[2-chloro-6-[[(R)-methylsulfinyl]methyl]pyrimidin-4-yl]-3-methyl-morpholine

STR1 STR2

Synthesis of (3R)-4-[2-chloro-6-[[(R)-methylsulfinyl]methyl]pyrimidin-4-yl]-3-methyl-morpholine (10)

off-white solid (53.9 kg, 68.3% yield). 1H NMR (400 MHz, DMSO-d6, δ): 1.20 (d, J = 6.8 Hz, 3 H), 2.52 (m, 1 H), 2.63 (s, 3 H), 3.21 (m, 1 H), 3.44 (m, 1 H), 3.58 (dd, J = 11.6, 3.1 Hz, 1 H), 3.72 (d, J = 11.5 Hz, 1 H), 3.92 (m, 3 H), 4.07 (d, J = 12.4 Hz, 1 H), 6.80 (s, 1 H); Assay (HPLC) 99%; Assay (QNMR) 100%; Chiral purity (HPLC) (R,R)-diastereoisomer 99.6%, (R,S)-diastereoisomer 0.4%.

 

Abstract Image

A Baeyer–Villiger monooxygenase enzyme has been used to manufacture a chiral sulfoxide drug intermediate on a kilogram scale. This paper describes the evolution of the biocatalytic manufacturing process from the initial enzyme screen, development of a kilo lab process, to further optimization for plant scale manufacture. Efficient gas–liquid mass transfer of oxygen is key to obtaining a high yield.

Development and Scale-up of a Biocatalytic Process To Form a Chiral Sulfoxide

The Departments of Pharmaceutical Sciences and Pharmaceutical Technology and Development, AstraZeneca, Silk Road Business Park, Macclesfield, Cheshire SK10 2NA, United Kingdom
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.6b00391
Publication Date (Web): January 4, 2017
Copyright © 2017 American Chemical Society
*Tel: +44 (0)1625-519149. E-mail: william.goundry@astrazeneca.com.
Figure
Examples of biologically active molecules containing a sulfoxide or sulfoximine: esomeprazole (3), aprikalim (4), oxisurane (5), OPC-29030 (6), ZD3638 (7), buthionine sulfoximine (8), and AZD6738 (9).

“ALL FOR DRUGS” CATERS TO EDUCATION GLOBALLY, No commercial exploits are done or advertisements added by me. This article is a compilation for educational purposes only.

P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent

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(±)-trans-ethyl 2-(3,4-difluorophenyl)Cyclopropanecarboxylate

 spectroscopy  Comments Off on (±)-trans-ethyl 2-(3,4-difluorophenyl)Cyclopropanecarboxylate
Feb 092017
 

STR1 STR2 STR3

(±)-trans-ethyl 2-(3,4-difluorophenyl)Cyclopropanecarboxylate

C12H12F2O2

GC-MS (EI) m/z: [M]+ calc. for C12H12F2O2 + : 226.08; found: 226.08.

δH (400 MHz, CDCl3): 1.25 (1H, ddd, 3 J 8.4 Hz, 3 J 6.4 Hz, 2 J 4.5 Hz , 3-H); 1.28 (3H, t 3 J 6.4 Hz CH3Ethyl) 1.57-1.62 (2H, m, 3 J 9.2 Hz, 3 J 5.2 Hz, 2 J 4.5 Hz, 3-H + H2O), 1.84 (1H, ddd, 3 J 8.5 Hz, 3 J 5.3 Hz, 3 J 4.3 Hz , 2-H), 2.47 (1H, ddd, 3 J 9.5 Hz, 3 J 6.4 Hz, 3 J 4.2 Hz , 1-H), 4.17 (2H, q, 3 J 6.3 Hz, CH2Ethyl) 6.81-6.87 (1H, m, 3 J 8.5 Hz, 4 J 7.6 Hz, 4 J 2.4 Hz, 6-H’ ), 6.88 (1H, ddd, 3 J 11.5 Hz, 4 J 7.6 Hz, 4 J 2.2 Hz, 2-H’) 7.06 (1H, dt, 3 J 10.3 Hz, 3 J 8.2 Hz. 5-H’).

δc (400 MHz, CDCl3): 14.27 (CH3Ethyl), 16.84 (3-C) 24.04 (1-C), 25.14 (d, 4 J 1.4, 2-C), 60.71 (CH2Ethyl), 114.74 (d, 2 J 19 Hz, 2-C’), 117.09 (d, 2 J 18 Hz, 5-C’), 122.25 (dd, 3 J 6.1 Hz, 4 J 3.4 Hz, 6- C’), 137.06 (dd, 3 J 6.1 Hz, 4 J 3.4 Hz, 1- C’), 149.2 (dd, 1 J 248 Hz, 2 J 13 Hz, 4-C’) 151.32 (dd, 1 J 249 Hz, 2 J 12.5 Hz, 3-C’) 172.87 (Ccarbonyl).

[ ] 20 a D = -381.9 (c 1.0 in EtOH) for (1R,2R)-3, ee = 95%

Abstract Image

In this study a batch reactor process is compared to a flow chemistry approach for lipase-catalyzed resolution of the cyclopropanecarboxylate ester (±)-3. (1R,2R)-3 is a precursor of the amine (1R,2S)-2 which is a key building block of the API ticagrelor. For both flow and batch operation, the biocatalyst could be recycled several times, whereas in the case of the flow process the reaction time was significantly reduced.

Comparison of a Batch and Flow Approach for the Lipase-Catalyzed Resolution of a Cyclopropanecarboxylate Ester, A Key Building Block for the Synthesis of Ticagrelor

School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, United Kingdom
Chemessentia, SRL – Via G. Bovio, 6-28100 Novara, Italy
§ Institute of Process Research and Development, School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, United Kingdom
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.6b00346
Publication Date (Web): December 22, 2016
Copyright © 2016 American Chemical Society

“ALL FOR DRUGS” CATERS TO EDUCATION GLOBALLY, No commercial exploits are done or advertisements added by me. This article is a compilation for educational purposes only.

P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent

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2,2′-(1-(tert-Butoxycarbonyl)pyrrolidine-3,4-diyl)diacetic Acid

 spectroscopy, SYNTHESIS, Uncategorized  Comments Off on 2,2′-(1-(tert-Butoxycarbonyl)pyrrolidine-3,4-diyl)diacetic Acid
Feb 012017
 

 

STR1

2,2′-(1-(tert-Butoxycarbonyl)pyrrolidine-3,4-diyl)diacetic Acid

STR1 STR2 STR3 str4 str5

2,2′-(1-(tert-Butoxycarbonyl)pyrrolidine-3,4-diyl)diacetic Acid 

as a white solid. Mp: 162–163 °C, % purity: 94.09% (HPLC);
1H NMR (DMSO-d6, 400 MHz) δ: 1.38 (s, 9H), 2.10–2.18 (m, 2H), 2.28–2.32 (m, 2H), 2.49–2.50 (m, 2H, merged with DMSO peak), 2.97–3.03 (m, 2H), 3.33–3.40 (m, 2H), 12.23 (bs, 2H); 1H NMR (CD3OD, 400 MHz) δ: 1.46 (s, 9H), 2.26 (ddd, J1 = 2.8 Hz, J2 = 9.2 Hz, J3 = 16.0 Hz, 2H), 2.43 (dd, J1 = 5.2 Hz, J2 = 16.0 Hz, 2H), 2.69 (m, 2H), 3.16 (dd, J1 = 5.2 Hz, J2 = 10.8 Hz, 2H), 3.49–3.54 (m, 2H);
13C NMR (DMSO-d6, 100 MHz) δ: 28.49, 32.97, 36.49, 37.31, 50.10, 50.20, 78.67, 154.05, 173.96;
IR (KBr): ν = 871, 933, 1143, 1166, 1292, 1411, 1689, 1708, 2881, 2929, 2980, 3001 cm–1;
TOFMS: [C13H21NO6 – H+]: calculated 286.1296, found 286.1031(100%).
HPLC conditions were as follows for compound ; Agilent 1100 series, column: YMC J’SPHERE C18 (150 mm X 4.6 mm) 4µm with mobile phases A (0.05% TFA in water) and B (acetonitrile). Detection was at 210 nm, flow was set at 1.0 mL/min, and the temperature was 30 °C (Run time: 45 min). Gradient: 0 min, A = 90%, B = 10%; 5.0 min, A = 90%, B = 10%; 25 min, A = 0%, B = 100%; 30 min, A = 0%, B = 100%, 35 min, A = 90%, B = 10%; 45 min, A = 90%, B = 10%.
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.6b00399
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Dimethyl 4,4′-(Benzylazanediyl)(2E,2′E)-bis(but-2-enoate)

 spectroscopy, SYNTHESIS, Uncategorized  Comments Off on Dimethyl 4,4′-(Benzylazanediyl)(2E,2′E)-bis(but-2-enoate)
Jan 312017
 

str5

Dimethyl 4,4′-(Benzylazanediyl)(2E,2′E)-bis(but-2-enoate)

STR1

IR (CHCl3): ν = 758, 1215, 1278, 1437, 1660, 1720, 2806, 2953, 3020, 3421 cm–1;

 

STR2

13C NMR (CDCl3, 100 MHz) δ: 51.53, 53.42, 58.37, 122.66, 127.28, 128.41, 128.55, 128.76, 138.24, 145.84, 166.58;

 

STR3

1H NMR (CDCl3, 400 MHz) δ: 3.23 (dd, J1 = 1.6 Hz, J2 = 6.0 Hz, 4H), 3.62 (s, 2H), 3.75 (s, 6H), 6.07 (dt, J1 = 1.6 Hz, J2 = 16.0 Hz, 2H), 6.97 (dt, J1 = 6.0 Hz, J2 = 16.0 Hz, 2H), 7.25–7.34 (m, 5H-merged with CDCl3 proton);

 

str4

TOFMS: [C17H21NO4 + H+]: calculated 304.1543, found 304.1703(100%).

str5

 

UPLC conditions were as follows for compound 11; Acquity Waters, column: BEH C18 (2.1 mm X 100 mm) 1.7 µm with mobile phases A (0.05% TFA in water) and B (acetonitrile). Detection was at 220 nm, flow was set at 0.4 mL/min, and the temperature was 30 °C (Run time: 9 min). Gradient: 0 min, A = 90%, B = 10%; 0.5 min, A = 90%, B = 10%; 6.0 min, A = 0%, B = 100%; 7.5 min, A = 0%, B = 100%; 7.6 min, A = 90%, B = 10%; 9.0 min, A = 90%, B = 10%.

 

Dimethyl 4,4′-(Benzylazanediyl)(2E,2′E)-bis(but-2-enoate) (11)

as a yellow oil. % purity: 93.4% (UPLC);
1H NMR (CDCl3, 400 MHz) δ: 3.23 (dd, J1 = 1.6 Hz, J2 = 6.0 Hz, 4H), 3.62 (s, 2H), 3.75 (s, 6H), 6.07 (dt, J1 = 1.6 Hz, J2 = 16.0 Hz, 2H), 6.97 (dt, J1 = 6.0 Hz, J2 = 16.0 Hz, 2H), 7.25–7.34 (m, 5H-merged with CDCl3 proton);
13C NMR (CDCl3, 100 MHz) δ: 51.53, 53.42, 58.37, 122.66, 127.28, 128.41, 128.55, 128.76, 138.24, 145.84, 166.58;
IR (CHCl3): ν = 758, 1215, 1278, 1437, 1660, 1720, 2806, 2953, 3020, 3421 cm–1;
TOFMS: [C17H21NO4 + H+]: calculated 304.1543, found 304.1703(100%).
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.6b00399
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1-Bromo-4-fluoro-2-((2-iodobenzyl)oxy)benzene

 Uncategorized  Comments Off on 1-Bromo-4-fluoro-2-((2-iodobenzyl)oxy)benzene
Jan 252017
 

STR1

1-Bromo-4-fluoro-2-((2-iodobenzyl)oxy)benzene

CAS 1161931-51-6

STR1 STR2

Mp 89.8–92.3 °C.

IR (neat, ATR): 3072 (w), 1482 (s), 1451 (s), 1294 (s), 1294 (s) cm–1.

1H NMR (399 MHz, DMSO-d6) δ 5.12 (s, 2H), 6.81 (td, J = 8.49, 2.77 Hz, 1H), 7.14 (td, J = 7.64, 1.65 Hz, 1H), 7.18 (dd, J = 10.90, 2.82 Hz, 1H), 7.46 (td, J = 7.52, 0.92 Hz, 1H), 7.60 (dd, J = 7.64, 1.41 Hz, 1H), 7.62 (dd, J = 8.66, 6.23 Hz, 1H), 7.92 (dd, J = 7.83, 0.83 Hz, 1H).

13C NMR (100 MHz, DMSO-d6) δ 74.5, 99.2, 102.4 (d, J = 27.1 Hz), 105.8 (d, J = 3.4 Hz), 108.9 (d, J = 22.5 Hz), 128.5, 129.8, 130.3, 133.6 (d, J = 9.9 Hz), 138.0, 139.2, 155.4 (d, J = 10.7 Hz), 162.2 (d, J = 244.3 Hz).

GCMS: m/z [M]+ calcd for C13H9BrFIO: 405.88600; found: 405.88620.

1H AND 13C NMR PREDICT

STR1 STR2 STR3 str4

 

Org. Process Res. Dev., Article ASAP

“ALL FOR DRUGS” CATERS TO EDUCATION GLOBALLY, No commercial exploits are done or advertisements added by me. This article is a compilation for educational purposes only.

P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent

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Brc2ccc(F)cc2OCc1ccccc1I
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Synthesis of (E)-2,4-Dinitro-N-((2E,4E)-4-phenyl-5-(pyrrolidin-1-yl)penta-2,4-dienylidene)aniline

 spectroscopy, SYNTHESIS, Uncategorized  Comments Off on Synthesis of (E)-2,4-Dinitro-N-((2E,4E)-4-phenyl-5-(pyrrolidin-1-yl)penta-2,4-dienylidene)aniline
Dec 212016
 

str1

Cas 1204588-48-6
MF C21 H20 N4 O4
MW 392.41
Benzenamine, 2,​4-​dinitro-​N-​[(2E,​4E)​-​4-​phenyl-​5-​(1-​pyrrolidinyl)​-​2,​4-​pentadien-​1-​ylidene]​-​, [N(E)​]​-
(E)-2,4-Dinitro-N-((2E,4E)-4-phenyl-5-(pyrrolidin-1-yl)penta-2,4-dienylidene)aniline
str1

 

 

Molbank 2009, 2009(3), M604; doi:10.3390/M604

Synthesis of (E)-2,4-Dinitro-N-((2E,4E)-4-phenyl-5-(pyrrolidin-1-yl)penta-2,4-dienylidene)aniline
Nosratollah Mahmoodi 1,*, Manuchehr Mamaghani 1, Ali Ghanadzadeh 2, Majid Arvand 3 and Mostafa Fesanghari 1
1Laboratory of Organic Chemistry, Faculty of Science, University of Guilan, P.O.Box 1914, Rasht, Iran,
2Departments of Physical Chemistry, Faculty of Science, University of Guilan, P.O.Box 1914, Rasht, Iran
3Departments of Analytical Chemistry, Faculty of Science, University of Guilan, P.O.Box 1914, Rasht, Iran
*Author to whom correspondence should be addressed
mahmoodi@guilan.ac.ir, m-chem41@guilan.ac.ir, aggilani@guilan.ac.ir, arvand@guilan.ac.ir, nosmahmoodi@gmail.com

Abstract:

(E)-2,4-Dinitro-N-((2E,4E)-4-phenyl-5-(pyrrolidin-1-yl)penta-2,4-dienylidene) aniline dye was prepared in one pot by reaction of premade N-2,4-dinitrophenyl-3-phenylpyridinium chloride (DNPPC) and pyrrolidine in absolute MeOH.
Keywords:

N-2,4-dinitrophenyl-3-phenylpyridinium chloride (DNPPC); photochromic; pyridinium salt

N-2,4-Dinitrophenyl-3-phenylpyridinium chloride (DNPPC) 1 was prepared according to the literature method [1,2,3,4,5,6,7]. Recently, we became interested in the synthesis of photochromic compounds [8,9,10]. The UV-Vis spectra under irradiation of UV light of dye 2 indicate photochromic properties for this molecule. The salt 1 was premade and typically isolated and purified by recrystallization and characterized. To a solution of 1-chloro-2,4-dinitrobenzene (1.42 g, 7.01 mmol) in acetone (10 mL) was added 3-phenylpyridine (1.0 mL, 6.97 mmol). The reaction was heated at reflux for 48 h. The solvent was removed under reduced pressure and the red residue was stirred in hexanes. The precipitated product was collected by vacuum filtration to afford pure pyridinium salt 1 as a reddish brown solid (2.23 g, 6.25 mmol, 90%). 1H NMR (CDCl3, 500 MHz): δ (ppm) 9.9 (s, 1H), 9.4 (d, J = 6.0 Hz, 1H), 9.3 (d, J = 8.3 Hz, 1H), 9.2 (d, J = 2.2 Hz, 1H), 9.0 (dd, J = 8.7, 2.4 Hz, 1H), 8.5-8.6 (m, 2H), 8.0 (d, J = 7.3 Hz, 2H), 7.6- 7.7 (m, 3H); 13C NMR (CDCl3, 125 MHz): δ (ppm) 149.2, 145.6, 144.3, 144.2, 143.0, 139.2, 138.7, 132.5, 132.3, 130.6, 130.2, 129.6, 128.0, 127.6, 121.3; IR (KBr pellet) 3202, 3129, 2994, 2901, 1609 cm-1; m. p. = 182-183 °C; HRMS m/z Calcd for C17H12N3O4+ (M)+ 322.0828, found 322.0836.
Molbank 2009 m604 i001
Reaction of pyrrolidine with salt (1) leads to the opening of the pyridinium ring and formation of dye 2. This dye was prepared from reaction of salt 1 (0.5 g, 1.4 mmol) in 5 mL absolute MeOH after cooling a reaction mixture to -10oC and keeping at this temperature for 15 min. To this was added pyrrolidine (0.1 g, 1.4 mmol) in 3 mL absolute MeOH over a period of 10 min. The prepared solid was filtered, washed with CH2Cl2, dried and recrystallized from n-hexane to yield 68% (0.37 g, 0.95 mmol) of pure metallic greenish-brown 2,
m.p. = 146 oC.
IR (KBr): 3040, 2950, 1616, 1514, 1492, 1469, 1321, 1215, 1170, 1105, 956, 904, 862, 727 cm-1.
1H NMR (500 MHz, CDCl3): δ (ppm) 8.7 (d, J = 2.4 Hz, 1H) 8.3 (dd, J = 2.4, 8.84 Hz, 1H), 8.0 (s, 1H), 7.5 (d, J = 7.4 Hz, 2H), 7.4-7.5 (t, J = 7.5 Hz, 2H), 7.3-7.4 (m, 1H), 7.2 (d, J = 12.5 Hz, 1H), 7.1 (d, J = 8.9 Hz, 1H), 7.0 (d, J = 12.1 Hz, 1H), 5.4 (t, J = 12.2 Hz, 1H), 3.3 (br, 4H), 2.0 (br, 4H);
13C NMR (125 MHz, CDCl3): δ (ppm) 22.0, 55.6, 114.7, 117.4, 120.0, 124.1, 126.4, 128.7, 128,8, 129.0, 132.7, 137.1, 137.3, 142.9, 147.8, 150.2, 163.8.
Anal. Calcd for C21H20N4O4: %C = 64.28, %H = 5.14, %N = 14.28. Found: %C = 64.08, %H = 5.11, %N = 14.07.

str1

 

 

1H NMR PREDICT

str0

ACTUAL….

1H NMR (500 MHz, CDCl3): δ (ppm) 8.7 (d, J = 2.4 Hz, 1H) 8.3 (dd, J = 2.4, 8.84 Hz, 1H), 8.0 (s, 1H), 7.5 (d, J = 7.4 Hz, 2H), 7.4-7.5 (t, J = 7.5 Hz, 2H), 7.3-7.4 (m, 1H), 7.2 (d, J = 12.5 Hz, 1H), 7.1 (d, J = 8.9 Hz, 1H), 7.0 (d, J = 12.1 Hz, 1H), 5.4 (t, J = 12.2 Hz, 1H), 3.3 (br, 4H), 2.0 (br, 4H);

str0

 

13 C NMR PREDICT

 

str1

ACTUAL…….13C NMR (125 MHz, CDCl3): δ (ppm) 22.0, 55.6, 114.7, 117.4, 120.0, 124.1, 126.4, 128.7, 128,8, 129.0, 132.7, 137.1, 137.3, 142.9, 147.8, 150.2, 163.8.

str3

////////////Synthesis, (E)-2,4-Dinitro-N-((2E,4E)-4-phenyl-5-(pyrrolidin-1-yl)penta-2,4-dienylidene)aniline

[O-][N+](=O)c3ccc(\N=C\C=C\C(=C/N1CCCC1)c2ccccc2)c([N+]([O-])=O)c3

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NMR, 3-[3-(benzoylamino)-4-hydroxylphenyl] propanoic acid

 spectroscopy  Comments Off on NMR, 3-[3-(benzoylamino)-4-hydroxylphenyl] propanoic acid
Jul 022015
 

 

 

http://www.google.com/patents/WO2008022462A1?cl=en

 

1 H-NMR Spectrum of Compound 35…………3-[3-(benzoylamino)-4-hydroxylphenyl] propanoic acid

1H-NMR (Acetone-D6) δ: 2.60 (t, 2H, J = 7.4, H- 3), 2.84 (t, 2H, J = 7.9, H-2), 6.89 (d, IH, J = 8.2, H-8), 7.00 (dd, IH, J = 2.1 , 8.25, H- 9), 7.57 (m, 4H, H-5, H-4′, H-5′, H-61), 8.05 (d, 2H, J = 8.2, H-3′, H-7′), 9.07 (broad s, IH, NH), 9.54 (broad s, IH, OH), 10.58 (broad s, IH, CO2H).

Figure imgf000063_0001
Figure imgf000063_0002

13C-NMR Spectrum of Compound 35

13C-NMR (Acetone- D6) δ: 30.87 (C- 3), 36.21 (C- 2), 118.69 (C- 8), 123.31 (C-5), 123.41 (C- 6), 126.88 (C- 9), 127.37 (C- 4), 128.54 (C-41, C-61), 129.61 (C-31, C-7′), 132.99 (C-51), 134.99 (C-21), 148.03 (C-7), 167.34 (C-I1), 173.94 (C-I ).

Figure imgf000064_0001
Figure imgf000064_0002

13C-NMR Spectrum of Compound 35

Figure imgf000065_0001
Figure imgf000065_0002

COSY-NMR Spectrum of Compound 35

Figure imgf000066_0001
Figure imgf000066_0002

COSY-NMR Spectrum of Compound 35

 

Figure imgf000067_0001

HETCOR-NMR Spectrum of Compound 35

 

Figure imgf000068_0001

 

 

3-[3-(benzoylamino)-4-hydroxylphenyl] propanoic acid 35:

 

To a solution of 32 (222 mg, 1.06 mmol, leq.) dissolved in THF (20 mL) was added the catalyst 10 % palladium-on-charcoal (15 % by mass, 33 mg). The resulting mixture was then placed on a hydrogenator, flushed (5 times) with hydrogen and left to agitate under pressure (36 psi.) overnight (12 hrs) while recharging hydrogen pressure twice (36 psi.) until hydrogen up-take by reaction mixture stopped (pressure did not decrease for 1-2 hrs.). The reaction mixture was vacuum filtered through Celite ‘ rinsing with THF. To the filtered solution containing 33 was directly added BzCl (154 mg, 1.1 mmol, 1 eq.) and left to stir at room temperature for 30 min. Then 10 % HCl (25 mL) was added and stirring continued an additional 5 min. followed by extraction with CIT2Cl2 (2 x 35 mL). The organic fractions were combined, dried (MgSO4), and evaporated off solvent. The resulting mixture was re-crystallized with Hexane/ Acetone to afford an off white solid (250 mg) with an 83 % yield from compound 32. Molecular Formula – C16Hi5NO4. Formula Weight – 285.295 g mole“1.

FT-IR (KBR disk) cm” 1 : 3201 (NH, OH), 1692 (CO2H), 1636 (NHAc).

1H-NMR (Acetone-D6) δ: 2.60 (t, 2H, J = 7.4, H- 3), 2.84 (t, 2H, J = 7.9, H-2), 6.89 (d, IH, J = 8.2, H-8), 7.00 (dd, IH, J = 2.1 , 8.25, H- 9), 7.57 (m, 4H, H-5, H-4′, H-5′, H-61), 8.05 (d, 2H, J = 8.2, H-3′, H-7′), 9.07 (broad s, IH, NH), 9.54 (broad s, IH, OH), 10.58 (broad s, IH, CO2H).

13C-NMR (Acetone- D6) δ: 30.87 (C- 3), 36.21 (C- 2), 118.69 (C- 8), 123.31 (C-5), 123.41 (C- 6), 126.88 (C- 9), 127.37 (C- 4), 128.54 (C-41, C-61), 129.61 (C-31, C-7′), 132.99 (C-51), 134.99 (C-21), 148.03 (C-7), 167.34 (C-I1), 173.94 (C-I ).

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1H-NMR Spectrum of Compound (+/-V36

Figure imgf000069_0001
Figure imgf000069_0002

13 C-NMR Spectrum of Compound (+/-V36

Figure imgf000070_0001
Figure imgf000070_0002

N-(l-oxaspiro[4.5]deca-6,9-dien-2,8-dion-7-yl)acetamide (+/-)-36: To a solution of 34 (122 mg, .547 mmol, 1 eq.) dissolved in acetone (10 mL, 0 0C) was added PIFA (306 mg, .71 1 mmol, 1.3 eq.) in one portion and stirred for 20-25 minutes (confirmed by tic: [1 : 1] EtOAc/Hexane). The reaction mixture was diluted with ethyl acetate (15 mL), washed with cold water (10 mL), dried organic fraction (MgSO4) and evaporated off solvent to afford a Tan solid. The crude product was purified by re-dissolving with CHCI3, filtering of the solution through Celite ®, evaporating off the solvent and placing it under vacuum overnight to afford an off white solid (120 mg, 98 % yield). Molecular Formula – C1 1Hi iNO4. Formula Weight – 221.209 g mole“1. FT-IR (KBR disk) cm“1: 3333 (NH), 1777 (lactone), 1668 (amide), 1650 (ketone), 1620 (α, β-conjugation to ketone). 1H-NMR (CDCl3) δ: 2.17 (s, 3H, H-2′), 2.44 (m, 2H, H-4), 2.81 (m, 2H, H-3), 6.35 (d, IH, J = 10.0, H-9), 6.94 (dd, IH, J = 3.1, 10.0, H- 10), 7.75 (d, IFI, J = 3.1, H-6), 7.99 (broad s, IH, NH). 13C-NMR (CDCl3) δ: 24.86 (C- 2′), 28.36 (C- 4), 32.91 (C- 3), 79.76 (C-5), 124.30 (C- 6), 127.12 (C- 9), 131.55 (C- 7), 148.37 (C-10), 169.51 (C-I’), 175.46 (C-2), 179.40 (C- 8).

 

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1H-NMR Spectrum of Compound 32

Figure imgf000059_0001
Figure imgf000059_0002

(2E)-3-(4-hydroxyl-3-nitrophenyl) acrylic acid 32: To a solution of 4- hydroxyl-3-nitrobenzaldehyde (1.073 g, 6.43 mmol, 1 eq.) dissolved in pyridine (25 mL) was added piperidine (25 drops) and the resulting mixture was stirred (4-5 min.). Malonic acid (1.671 g, 16.1 mmol, 2.5 eq.) was then added in one portion and the resulting mixture was warmed (60-63 0C) and stirred overnight (12-14 hrs, confirmed by tic: EtOAc, mini work up, 10 % HCl and EtOAc). The reaction was cooled and acidified (50 % HCl) until yellow precipitate formed (pH~2). This yellow precipitate was extracted with ethyl acetate (2 x 150 niL). The organic fractions were combined and washed with brine (150 mL), dried (MgSO4), and the solvent was evaporated to afford a yellow solid. Removed excess solvent by vacuum and used without further purification (1.250 g, 93 % yield). Molecular Formula – CgH7NO5. Formula Weight – 209.156 g mole“1. FT-IR (KBR disk) cm“1: 2942 (OH), 1684 (CO2H), 1626 (C=C), 1533,1270 (NO2). 1FI-NMR (Acetone-D6) δ: 2.87 (broad s, IH, OH), 6.58 (d, IH, J= 16.0, H-2), 7.27 (d, IH, J= 8.8, H-8), 7.70 (d, IH, J= 16.4, H-3), 8.08 (d, IH, J= 2.2, 8.5, H-9), 8.40 (d, IFI, J = 2.2, FI-5), 10.67 (broad s, I H, CO2FI). The13C-NMR of this compound agrees with the previously published data.52

 

 

 

Con Dao Island, Vietnam

 

con dau six senses resort image

Con Dao Island, Vietnam

 

This 16-island archipelago is a “pocket of paradise,” says Robert Reid, a travel editor at Lonely Planet.

Getting there: Take a 45-minute flight from Ho Chi Minh City.

What to do: The diving is among the best in Vietnam. Take scuba lessons as a couple or discover the nearby secluded beaches of Bai Dat Doc and Dam Trau.

Where to stay: Six Senses resort offers luxury villas on the East Vietnam Sea. The resort has an in-house spa offering traditional Vietnamese healing practices; it also boasts outdoor treatment rooms and a yoga and meditation pavilion. Inquire for rates.

 

Con Dao travel guide – Wikitravel

wikitravel.org/en/Con_Dao

Con Dao is an island off the southern coast of Vietnam. … The Con Dao Islands separated from the mainland about 15,000 years ago. This has resulted in the …

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NMR Structure Elucidation of Small Organic Molecules and Natural Products: Choosing ADEQUATE vs HMBC

 Uncategorized  Comments Off on NMR Structure Elucidation of Small Organic Molecules and Natural Products: Choosing ADEQUATE vs HMBC
Jun 092015
 
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Long-range heteronuclear shift correlation methods have served as the cornerstone of modern structure elucidation protocols for several decades. The 1H–13C HMBC experiment provides a versatile and relatively sensitive means of establishing predominantly 3JCHconnectivity with the occasional 2JCH or 4JCH correlation being observed. The two-bond and four-bond outliers must be identified specifically to avoid spectral and/or structural misassignment. Despite the versatility and extensive applications of the HMBC experiment, it can still fail to elucidate structures of molecules that are highly proton-deficient, e.g., those that fall under the so-called “Crews rule”. In such cases, recourse to the ADEQUATE experiments should be considered. Thus, a study was undertaken to facilitate better investigator understanding of situations where it might be beneficial to apply 1,1- or 1,n-ADEQUATE to proton-rich or proton-deficient molecules. Equipped with a better understanding of when a given experiment might be more likely to provide the necessary correlation data, investigators can make better decisions on when it might be advisible to employ one experiment over the other. Strychnine (1) and cervinomycin A2 (2) were employed as model compounds to represent proton-rich and proton-deficient classes of molecules, respectively. DFT methods were employed to calculate the relevant nJCHheteronuclear proton–carbon and nJCC homonuclear carbon–carbon coupling constants for this study.

NMR Structure Elucidation of Small Organic Molecules and Natural Products: Choosing ADEQUATE vs HMBC

† Discovery and Preclinical Sciences, Process and Analytical Chemistry, NMR Structure Elucidation, Merck Research Laboratories, Kenilworth, New Jersey 07033, United States
‡ Discovery and Preclinical Sciences, Process and Analytical Chemistry, NMR Structure Elucidation, Merck Research Laboratories, Rahway, New Jersey 07065, United States
J. Nat. Prod., 2014, 77 (8), pp 1942–1947
DOI: 10.1021/np500445s
*Tel: 908-740-3990. Fax: 908-740-4042. E-mail: alexei.buevich@merck.com.
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Using HMBC and ADEQUATE NMR Data To Define and Differentiate Long-Range Coupling Pathways: Is the Crews Rule Obsolete?
It is well known that as molecules become progressively more proton-deficient, structure elucidation becomes correspondingly more challenging. When the ratio of 1H to 13C and the sum of other heavy atoms falls below 2, an axiom that has been dubbed the “Crews rule” comes into play. The general premise of the Crews rule is that highly proton-deficient molecules may have structures that are difficult, and in some cases impossible, to elucidate using conventional suites of NMR experiments that include proton and carbon reference spectra, COSY, multiplicity-edited HSQC, and HMBC (both 1H–13C and 1H–15N). However, with access to modern cryogenic probes and microcyroprobes, experiments that have been less commonly utilized in the past and new experiments such as inverted 1JCC 1,n-ADEQUATE are feasible with modest sized samples. In this light, it may well be time to consider revising the Crews rule. The complex, highly proton-deficient alkaloid staurosporine (1) is used as a model proton-deficient compound for this investigation to highlight the combination of inverted 1JCC 1,n-ADEQUATE with 1.7 mm cryoprobe technology.

Using HMBC and ADEQUATE NMR Data To Define and Differentiate Long-Range Coupling Pathways: Is the Crews Rule Obsolete?

Gary E Martin
† Discovery and Preclinical Sciences, Process and Analytical Chemistry, Structural Elucidation Group, Merck Research Laboratories, Kenilworth, New Jersey 07033, United States
‡ Discovery and Preclinical Sciences, Process and Analytical Chemistry, Structural Elucidation Group, Merck Research Laboratories, Rahway, New Jersey 07065, United States
§ Discovery and Preclinical Sciences, Process and Analytical Chemistry, Structural Elucidation Group, Merck Research Laboratories, Summit, New Jersey 07901, United States
J. Nat. Prod., 2013, 76 (11), pp 2088–2093
DOI: 10.1021/np400562u
Publication Date (Web): November 6, 2013
Copyright © 2013 The American Chemical Society and American Society of Pharmacognosy
*Phone: 908-473-5398. Fax: 908-473-6559. E-mail: gary.martin2@merck.com.
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KETO ENOL TAUTOMERISM AND NMR

 spectroscopy, Uncategorized  Comments Off on KETO ENOL TAUTOMERISM AND NMR
Jun 032015
 

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H Nmr Spectrum | Apk Mod Game

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Shows a method for getting all the useful information out of a proton nmr spectrum and using it to piece together the identity of an unknown molecule.
A Partial NMR Spectrum of 2,4-Pentanedione

 

 

 

 

 

 

 

Patent EP0922715B1 – Stimuli-responsive polymer utilizing keto …

Carbonyl compounds (aldehydes, ketones, carboxylic esters, carboxylic amides) react aselectrophiles at the sp2 hybridized carbon atoms and as nucleophiles if they contain an H-atom in the α-position relative to their C=O or C=N bonds. This is because this H is acidic and it can be removed by a base leaving behind an electron pair for nucleophilic attacks.

For most compounds in organic chemistry all the molecules have the same structure – even if this structure cannot satisfactory represented by a Lewis formula – but for many compounds there is a mixture of two or more structurally distinct compounds that are in rapid equilibrium. This phenomenon is called tautomerism.

Tautomerism is the phenomenon that occurs in any reaction that simply involves the intramolecular transfer of a proton. An equilibrium is established between the two tautomers (structurally distinct compounds) and there is a rapid shift back and forth between the distinct compounds.

A very common form of tautomerism is that between a carbonyl compound containing an αhydrogen and its enol form (Fig. I.1).

Fig. I.1: A keto-enol reaction
Fig. I.1: A keto-enol reaction

 

An enol is exactly what the name implies: an ene-ol. It has a C=C double bond (diene) and an OH group (alcohol) joined directly to it.

Notice that in the above reaction as in any keto-enol reaction there is no change in pH since a proton is lost from carbon and gained on oxygen. The reaction is known as enolization as it is the conversion of a carbonyl compound into its enol.

Notice also that in the above reaction the product is almost the same as the starting material since the only change is the transfer of one proton and the shift of the double bond.

In simple cases (R2 = H, alkyl, OR, etc.) the equilibrium of the keto-enol reaction lies well to the left (keto structure) (Table I.1). The reason can be seen by examining the bond energies in Table I.2.

 

Compound

Enol Content, %

Acetone

6 * 10-7

PhCOCH3

1.1 * 10-6

CH3CHO

6 * 10-5

Cyclohexanone

4 * 10-5

Ph2CHCHO

9.1

PhCOCH2COCH3

89.2

Table I.1: The enol content of some carbonyl compounds

 

If keto-enol reactions are common for aldehydes and ketones why don’t simple aldehydes and ketones exist as enols?

IR and NMR Spectra of carbonyl compounds show no signs of enols. The equilibrium lies well over towards the keto form (the equilibrium constant k for cyclohexanone is about 10-5).

 

Bond (Energy, kJ/mol)

Sum ( kJ/mol)

keto form

C-H (413)

C-C (350)

C=O (740)

1503

enol form

C=C (620)

C-O (367)

O-H (462)

1449

Table I.2: Bond energies in the keto and in the enol form. The keto form is thermodynamically more stable than the enol form by approximately 50 kJ/mol

The approximate sum of the bond energies in the keto form is 1503 kJ/mol while in the enol form 1449. Therefore, the keto form is thermodynamically more stable than the enol form by approximately 50 kJ/mol.

In most cases, enol forms cannot be isolated since they are less stable and are formed in minute quantities. However, there are some exceptions and in certain cases a larger amount of the enol form is present and it can be even the predominant species:

  • Molecules in which the enolic double bond is in conjugation with another double bond (cases are shown in Table I.1 like Ph2CHCHO and PhCOCH2COCH3)
  • Molecules that contain two or more bulky aryl groups (Fig. I.2). Compound I in Fig. I.2 (a substituted enol) is the major species in equilibrium (~95%) while the keto form is the minor species (~5%). In cases like this steric hindrance destabilizes the keto form (the two substituted aryl groups are 109° apart) while in the enol form 120° apart.

 

Fig. I.2: A keto-enol reaction. The enol form (I) is the major species since the keto form is destabilized by steric hindrance (the substituted aryl groups are closer in the keto form – the C-C angle is 109° and this is unfavorable due to steric hindrance)
Fig. I.2: A keto-enol reaction. The enol form (I) is the major species in this case since the keto form is destabilized by steric hindrance (the substituted aryl groups are closer in the keto form – the C-C angle is 109° and this is unfavorable due to steric hindrance)

 

Is there experimental evidence that keto-enol reactions are common for aldehydes and ketones?

If the NMR spectrum of a simple carbonyl compound in D2O is obtained – such as pinacolone’s (CH3)3CCOCH3 – the signal for protons next to the carbonyl group very slowly disappears. The isolated compound’s mass spectrum (after the above mentioned reaction with D2O is over) shows that those hydrogen atoms have been replaced by deuterium atoms. There is a peak at (M+1)+ or (M+2)+ or (M+3)+ instead of M+. The reaction is shown in Fig. I.3:

 Fig. I.3: Evidence for a keto-enol reaction when pinacolone (CH3)3CCOCH3 reacts with D2O. When the enol form of the pinacolone reverts to the keto form it picks up a deuteron instead of a proton because the solution consists almost entirely of D2O.
Fig. I.3: Evidence for a keto-enol reaction when pinacolone (CH3)3CCOCH3 reacts with D2O. When the enol form of the pinacolone reverts to the keto form it picks up a deuteron instead of a proton because the solution consists almost entirely of D2O.

 

What mechanism can be proposed for the above reaction?

Enolization is a slow process in neutral solution, even in D2O, and is catalyzed by acid or base in order to happen.

In the acid-catalyzed reaction the molecule is first protonated on oxygen and then loses the C-H proton in a second step (Fig. I.4). When the enol form reverts to the keto – since this is an equilibrium process – it picks up a deuteron instead of a proton since the solution is D2O.

 

Fig. I.4: The acid-catalyzed keto-enol reaction mechanism. If D2O is the solvent then the α-hydrogens to carbonyl group are replaced by deuterium.
Fig. I.4: The acid-catalyzed keto-enol reaction mechanism. If D2O is the solvent then the α-hydrogens to carbonyl group are replaced by deuterium.

In the base-catalyzed reaction the C-H proton is removed first by the base (for example hydroxide ion OH, OD in our case) and the proton (or D+ in our case) added to the oxygen atom in a second step (Fig. I.5).

Fig. I.5: The base-catalyzed keto-enol reaction mechanism. If D2O is the solvent then the α-hydrogens to carbonyl group are replaced by deuterium.
Fig. I.5: The base-catalyzed keto-enol reaction mechanism. If D2O is the solvent then the α-hydrogens to carbonyl group are replaced by deuterium.

Notice that the enolization reactions in Fig. I.4 and Fig. I.5 are catalytic. In the acid-catalyzed mechanism the D+ (or H+ if water is the solvent) is regenerated at the end (catalyst). In the base-catalyzed mechanism OD (or OH if water is the solvent) is regenerated at the end (catalyst).

The enolate ion generated from the enol (Fig. I.6) in the base-catalyzed mechanism is nucleophilic due to:

  • Oxygen’s small atomic radius
  • Formal negative charge

An enolate ion is an ion with a negative charge on oxygen with adjacent C-C double bond.

 

 Fig. I.6: Enolate ion resonance contributors. Although the major contributor is resonace structure I when it reacts as a nucleophile structure II is more reactive.
Fig. I.6: Enolate ion resonance contributors. Although the major contributor is resonace structure I when it reacts as a nucleophile structure II is more reactive.

Enolates are reactive nucleophiles. Although the major enolate Lewis contributor shows concentration of electron density on the electronegative oxygen when it reacts as a nucleophile, it behaves like the electron density is concentrated on the α-carbon next to carbonyl group.

Enolates react with alkyl halides, aldehydes/ketones and esters and these reactions are shown in the post entitled “The chemistry of enolate ions – Enolate ion reactions”.


 

References
  1. A.J. Kresge, Pure Appl. Chem., 63, 213 (1991)
  2. B. Capon, The Chemistry of Enols, Wiley, NY, 307–322 (1990)
  3. S.E. Biali et al., J. Am. Chem. Soc. 107, 1007 (1985).

 

 

 

 

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http://www.slideshare.net/chemsant/nmr-dynamic

 

 

http://article.sapub.org/10.5923.j.ajoc.20140401.01.html

2-fluoro-3-hydroxycyclopent-2-enone and 2-fluoro- 1,3-cyclopentanedione (1c): This compound was obtained as a 52:48 mixture of keto-enol and diketo tautomers in 50% yield as a yellow-brown solid, mp 70-72°C. NMR:1H: δ 2.36 (t, 3JH-H = 16.2 Hz, 2H), 2.85 (m, 2H), 5.91 (d, 2JH-F = 47.7 Hz, 1H). 13C: δ31.1, 90.8 (d, 1JC-F = 251.3 Hz), 122.3 (d, 1JC-F = 233.9 Hz), 210.1 (d, 2JC-F = 31.0 Hz). 19F: keto-enol: δ-161.4 (s, 1F); diketo: δ-195.5 (d, 2JF-H = 47.7 Hz, 1F). Analysis calcd for C5H5FO2: C, 51.73, H, 4.34. Found: C, 51.48, H, 4.31.

 

 

 

 

 

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Kathiyavadi food, Garden Restaurant, Restaurant in surat, Restaurant, Restaurant Services, Food

 

 

 

 

 

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