DR ANTHONY MELVIN CRASTO,WorldDrugTracker, helping millions, A 90 % paralysed man in action for you, I am suffering from transverse mylitis and bound to a wheel chair, With death on the horizon, nothing will not stop me except God................DR ANTHONY MELVIN CRASTO Ph.D ( ICT, Mumbai) , INDIA 25Yrs Exp. in the feld of Organic Chemistry,Working for GLENMARK GENERICS at Navi Mumbai, INDIA. Serving chemists around the world. Helping them with websites on Chemistry.Million hits on google, world acclamation from industry, academia, drug authorities for websites, blogs and educational contribution
Showing posts with label nmr. Show all posts
Showing posts with label nmr. Show all posts

Friday 3 November 2017

An efficient green protocol for the synthesis of tetra-substituted imidazoles catalyzed by zeolite BEA: effect of surface acidity and polarity of zeolite

Image result for Kalpana C. Maheria sv
1-benzyl-2, 4, 5-triphenyl-1H-imidazole
STR1 STR2 str3
. 1-Benzyl-2,4,5-triphenyl-1H-imidazole (5a, n = 1).
Off-white solid; m.p.: 160–162 °C;
anal. calcd. for C28H22N2: C, 87.01, H, 5.74, N, 7.25%. Found: C, 87.13, H, 5.70, N, 7.19%;
UV (λmax, ethanol) = 280 nm;
FT-IR (KBr, cm−1 ): 3060 (C–H stretch), 3031, 1600 (CN), 1497, 1483, 1447 (CC), 1352 (C–N stretch), 769, 697 (C–H band);
1 H NMR (400 MHz, DMSO): 5.16 (s, 2H, CH2), 6.74–7.67 (m, 20H, Ar–H) ppm;
13C NMR (100 MHz, DMSO): 47.6 (CH2, C8), 125.1 (CHarom, C28), 126.0 (CHarom, C26), 126.2 (CHarom, C30), 126.4 (CHarom, C11), 127.0 (CHarom, C15), 127.1 (CHarom, C16), 127.7 (CHarom, C20), 128.0 (CHarom, C21), 128.1 (CHarom, C25), 128.4 (CHarom, C13), 128.5 (CHarom, C18), 128.6 (CHarom, C27), 128.8 (C1), 128.8 (CHarom, C12), 128.9 (CHarom, C14), 130.1 (CHarom, C17), 130.3 (CHarom, C19), 130.5 (CHarom, C22), 130.7 (CHarom, C24), 131.0 (CHarom, C29), 134.4 (CHarom, C9), 135.1 (CHarom, C23), 136.8 (CHarom, C7), 137.0 (CHarom, C10), 137.2 (CHarom, C6), 145.4 (C2), 147.0 (C4) ppm;
MS: m/z = 387.5 (M + H)+

An efficient green protocol for the synthesis of tetra-substituted imidazoles catalyzed by zeolite BEA: effect of surface acidity and polarity of zeolite

*Corresponding authors

Abstract

In the present study, the catalytic activity of various medium (H-ZSM-5) and large pore (H-BEA, H-Y, H-MOR) zeolites were studied as solid acid catalysts. The zeolite H-BEA is found to be an efficient catalyst for the synthesis of 1-benzyl-2,4,5-triphenyl-1H-imidazoles through one-pot, 4-component reaction (4-CR) between benzil, NH4OAc, substituted aromatic aldehydes and benzyl amine. The hydrophobicity, Si/Al ratio and acidic properties of zeolite BEA were well improved by controlled dealumination. The synthesized materials were characterized by various characterization techniques such as XRD, ICP-OES, BET, NH3-TPD, FT-IR, pyridine FT-IR, 27Al and 1H MAS NMR. It has been observed that the dealumination of the parent zeolite H-BEA (12) results in the enhanced strength of Brønsted acidity up to a certain Si/Al ratio which is attributed to the inductive effect of Lewis acidic EFAl species, leading to the higher activity of the zeolite BEA (15) catalyst towards the synthesis of 1-benzyl-2,4,5-triphenyl-1H-imidazoles under thermal solvent-free conditions with good to excellent yields. Using the present catalytic synthetic protocol, diverse tetra-substituted imidazoles, which are among the significant biologically active scaffolds, were synthesized in high yield within a shorter reaction time. The effect of polarity, surface acidity and extra framework Al species of the catalysts has been well demonstrated by means of pyridine FT-IR, and 27Al and 1H MAS NMR. The solvent-free synthetic protocol makes the process environmentally benign and economically viable.
Graphical abstract: An efficient green protocol for the synthesis of tetra-substituted imidazoles catalyzed by zeolite BEA: effect of surface acidity and polarity of zeolite
STR1
STR1
Image result for S. V. National Institute of Technology, Ichchhanath, Surat
Image result for S. V. National Institute of Technology, Ichchhanath, Surat
Image result for S. V. National Institute of Technology, Ichchhanath, Surat
S. V. National Institute of Technology, Ichchhanath, Surat
Image result for Mandvi Science College, Mandvi – 394160, Surat, India
Image result for Mandvi Science College, Mandvi – 394160, Surat, India
Mandvi Science College, Mandvi – 394160, Surat, India
////////

DISCLAIMER

“ORGANIC SPECTROSCOPY INT” CATERS TO EDUCATION GLOBALLY, No commercial exploits are done or advertisements added by me. This 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

Saturday 28 October 2017

(S)-2-(4-Chlorobenzoyl)-1,2,3,4-tetrahydrobenzo[e]pyrazino[1,2-a][1,4]diazepine-6,12(11H,12aH)-dione—Synthesis and Crystallographic Studies

Molbank 2017 m964 sch001





Synthesis of the (S)-2-(4-Chlorobenzoyl)-1,2,3,4-tetrahydrobenzo[e]pyrazino[1,2-a][1,4]diazepine-6,12(11H,12aH)-dione (4)

(S)-piperazine-2-carboxylic acid dihydrochloride (5, 700 mg, 3.45 mmol, 1 equiv.) was dispersed in 50 mL of 1:1 water:dioxane mixture and treated with sodium hydroxide (276 mg, 6.89 mmol, 2 equiv.). After dissolution of the starting material, 4-chlorobenzoyl chloride (6, 0.49 mL, 3.79 mmol, 1.1 equiv.) was added and reaction mixture was stirred in room temperature for 18 h. The next day, the disappearance of starting material and formation of (S)-4-(4-chlorobenzoyl)piperazine-2-carboxylic acid (7) was confirmed by LRMS-ESI spectra. Then, isatoic anhydride (8, 1.69 g, 10.34 mmol, 3 equiv.) was added, followed by addition of sodium carbonate (1.10 g, 10.34 mmol, 3 equiv.); the reaction mixture was heated in 60 °C for 18 h. The following day, formation of the (S)-1-(2-aminobenzoyl)-4-(4-chlorobenzoyl)piperazine-2-carboxylic acid 9 was confirmed by LRMS-ESI spectra. The volatiles were evaporated under reduced pressure, then the residue was co-evaporated with toluene (3 × 50 mL) and dissolved in dry DMF. For cyclization of 9, HATU (3.93 g, 10.34 mmol, 3 equiv.) and DIPEA (1.80 mL, 10.34 mmol, 3 equiv.) were added, and reaction mixture was stirred in room temperature for 18 h. The day after, the volatiles were evaporated under reduced pressure and residue was dissolved in water:ethyl acetate biphasic system. The organic phase was washed with water (2 × 50 mL), 0.5 M HCl (3 × 50 mL), saturated sodium bicarbonate (1 × 50 mL), and dried over magnesium sulphate. The crude product dissolved in ethyl acetate was evaporated with silica gel (2 g) and purified by column chromatography using hexane:ethyl acetate 2:8 v/v mixture, followed by pure ethyl acetate. Yield: 711 mg (56%). 1H-NMR (500 MHz, DMSO-d6): 10.55, 10.45 (2 × s, 2 × NH); 7.80–7.70 (m, 1H, HAr); 7.70–7.40 (m, 5H, HAr); 7.30–7.20 (m, 1H, HAr); 7.20–7.00 (m, 1H, HAr); 4.45–3.30 (m, 7H, 3 × CH2, 1 × CH); 13C-NMR (125 MHz, DMSO-d6): 170.5, 169.5, 166.6, 136.6, 135.0, 134.2, 132.3, 130.9, 129.3, 129.0, 128.5, 128.3, 125.6, 124.0, 120.9, 51.7, 42.7, 42.2, 38.2; HRMS (ESI): m/z [M + H]+ calcd. for C19H17ClN3O3: 370.09530, 372.09235, found: 370.09517, 372.09206; m.p. 248–250 °C.  = +290 (c 1.0, DMSO). IR (KBr): cm−1 3465, 3369, 3229, 3160, 3109, 3068, 2909, 2866, 1694, 1657, 1620, 1521, 1477, 1431, 1407, 1339, 1303, 1262, 1219, 1181, 1162, 1092, 1035, 1010.









Molbank 20172017(4), M964; doi: 10.3390/M964
Communication
(S)-2-(4-Chlorobenzoyl)-1,2,3,4-tetrahydrobenzo[e]pyrazino[1,2-a][1,4]diazepine-6,12(11H,12aH)-dione—Synthesis and Crystallographic Studies
Adam Mieczkowski 1,*, Damian Trzybiński 2, Marcin Wilczek 3, Mateusz Psurski 4Orcid, Maciej Bagiński 1,3, Bartosz Bieszczad 1,3, Magdalena Mroczkowska 1,3 and Krzysztof Woźniak 2
1
Institute of Biochemistry and Biophysics Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland
2
Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
3
Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
4
Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 12 R. Weigl, 53-114 Wroclaw, Poland
*
Correspondence: Tel.: +48-22-592-35-06; Fax: +48-22-592-21-90
Received: 12 October 2017 / Accepted: 25 October 2017 / Published: 27 October 2017

Abstract

: 
(S)-2-(4-Chlorobenzoyl)-1,2,3,4-tetrahydrobenzo[e]pyrazino[1,2-a][1,4]diazepine-6,12(11H,12aH)-dione was obtained in a three-step, one-pot synthesis, starting from optically pure (S)-2-piperazine carboxylic acid dihydrochloride. Selective acylation of the β-nitrogen atom followed by condensation with isatoic anhydride and cyclization with HATU/DIPEA to a seven-member benzodiazepine ring, led to the tricyclic benzodiazepine derivative. Crystallographic studies and initial biological screening were performed for the title compound.

Keywords:
 (S)-2-piperazinecarboxylic acid; tricyclic benzodiazepines; isatoic anhydride; cytotoxicity

http://www.mdpi.com/1422-8599/2017/4/M964/htm
file:///C:/Users/Inspiron/Downloads/molbank-2017-M964-s002.pdf


/////////

Wednesday 25 October 2017

Cross dehydrogenative coupling of N-aryltetrahydroisoquinolines (sp3 C-H) with indoles (sp2 C-H) using a heterogeneous mesoporous manganese oxide catalyst


Cross dehydrogenative coupling of N-aryltetrahydroisoquinolines (sp3 C-H) with indoles (sp2 C-H) using a heterogeneous mesoporous manganese oxide catalyst
Green Chem., 2017, Advance Article
DOI: 10.1039/C7GC01919J, Communication
B. Dutta, V. Sharma, N. Sassu, Y. Dang, C. Weerakkody, J. Macharia, R. Miao, A. R. Howell, S. L. Suib
We disclose a novel, heterogeneous catalytic approach for selective coupling of C1 of N-aryltetrahydroisoquinolines with C3 of indoles in the presence of mesoporous manganese oxides.

Cross dehydrogenative coupling of N-aryltetrahydroisoquinolines (sp3 C–H) with indoles (sp2 C–H) using a heterogeneous mesoporous manganese oxide catalyst

Biswanath Dutta

Ph.D Candidate
Chemistry

B.Sc. Chemistry, University of Calcutta, India, 2011
M.S. Chemistry, IIT Bombay, India, 2013
Group Member Since 2013
Research Area: Material synthesis, Catalysis

Image result for University of Connecticut S. L. Suib

Steven Suib

Professor
Emailsteven.suib@uconn.edu
Phone(860) 486-2797
Fax(860) 486-2981
Mailing AddressUniversity of Connecticut
Department of Chemistry
55 N. Eagleville Rd
Storrs, CT 06269
Office LocationCHEM A-313

Abstract

We disclose a novel, heterogeneous catalytic approach for selective coupling of C1 of N-aryltetrahydroisoquinolines with C3 of indoles in the presence of mesoporous manganese oxides. Our work involves a detailed mechanistic investigation of the reaction on the catalyst surface, backed by DFT computational studies, to understand the superior catalytic activity of manganese oxides.

////////////////////

Friday 20 October 2017

NMR EXAMPLES

Image result for nmr education

  • Figure 1Proton NMR of 100% Methyl Acetate


Image result for nmr education

 2Proton NMR of 100% Methyl Propionate







Proton NMR of 100% Methyl Butyrate






///////////

Ethyl(1R,2S,3S,4S)-2-(furan-2-yl)-3-nitro-6-oxobicyclo[2.2.2]octane-1-carboxylate



Ethyl(1R,2S,3S,4S)-2-(furan-2-yl)-3-nitro-6-oxobicyclo[2.2.2]octane-1-carboxylate


Compound 7 Ethyl(1R,2S,3S,4S)-2-(furan-2-yl)-3-nitro-6-oxobicyclo[2.2.2]octane-1-carboxylate To a solution of CAT 10 (128 mg, 0.37 mmol) and the nitroolefin 9 (3.1 g, 22.3 mmol) in 10 mL anhydrous CH2Cl2 at room temperature was added enone 8 (1.8 g, 10.7 mmol). The resulting mixture was stirred at the same temperature until enone 8 is consumed as indicated by TLC. Then DBU (0.34 mL, 3.20 mmol) was added and the mixture was allowed to stir at ambient temperature until completion as indicated by TLC. The solution was concentrated in vacuo and purified by flash chromatography on silica gel (Hexane / EtOAc = 20 / 1) to give 7 (2 g, 61% yield) as a yellow solid. [α]D 23 28.0 (c = 1.0, CHCl3).

1H NMR (400 MHz, CDCl3): δ 7.29 (d, J = 0.8 Hz, 1H), 6.27 (dd, J = 2.0 Hz, J = 3.2 Hz, 1H), 6.14 (d, J = 4.0 Hz, 1H), 4.93 (m, 1H), 4.57 (d, J = 4.4 Hz, 1H), 4.11 (m, 2H), 3.04-3.02 (m, 1H), 2.80-2.75 (m, 1H), 2.60- 2.54 (m, 1H), 2.33-2.29 (m, 1H), 1.88-1.72 (m, 2H), 1.33-1.23 (m, 1H), 1.21 (t, J = 7.2 Hz, 3H).

13C NMR (100 MHz, CDCl3): δ 204.1, 168.7, 151.8, 142.5, 110.5, 108.1, 88.3, 61.3, 56.3, 42.0, 40.8, 33.7, 26.9, 19.2, 13.8.

IR (thin film): 3435, 3141, 3120, 2996, 2959, 1715, 1653, 1621, 1557, 1505, 1473, 1443, 1408, 1371, 1336, 1301, 1336, 1301, 1270, 1236, 1142, 1120, 1083, 1062, 1074, 1045, 1045, 1011, 996, 960, 930, 892, 884, 867, 803, 753, 628, 600, 508, 436 cm-1 .

LRMS (ESI): 308.0 (M+H)+ , 330.0 (M+Na)+ .

 HRMS (ESI): calcd for C15H18O6N (M+H) + : 308.1129. Found: 308.1130.

 Melting point: 117-118 oC.



Concise asymmetric total synthesis of (−)-patchouli alcohol


 Author affiliations

Abstract

The asymmetric total synthesis of (−)-patchouli alcohol was accomplished in a concise manner. Key reactions include a highly diastereo- and enantioselective formal organocatalytic [4 + 2] cycloaddition reaction, a radical denitration reaction, and an oxidative carboxylation reaction. The formal synthesis of norpatchoulenol was achieved as well.
Graphical abstract: Concise asymmetric total synthesis of (−)-patchouli alcohol


/////////

Thursday 19 October 2017

2-Methyl-3-tosyl-1,2,3,4-tetrahydroquinazoline

Image result for NMR IN COLOUR



Two-dimensional proton–proton NMR correlation spectrum of 2-methyl-3-tosyl-1,2,3,4-tetrahydroquinazoline in acetone-d6. A colour code was used to highlight the observed H–H couplings.



image file: c6ra20886j-s2.tif


Scheme 2 Pd-mediated hydrolysis of triethylamine in the presence of 2-tosylaminomethylaniline (HATs) to yield 2-methyl-3-tosyl-1,2,3,4-tetrahydroquinazoline and di(acetato)bis(diethylamine)palladium(II).

2-Methyl-3-tosyl-1,2,3,4-tetrahydroquinazoline

Yield = 12.3 mg (41%). 1H NMR (400 MHz, dmso-d6): δ/ppm 7.56 (d, J = 8.2 Hz, 2H, 2 × H-2′), 7.16 (d, J = 8.1 Hz, 2H, 2 × H-3′), 6.83 (m, 2H, H-5 + H-7), 6.46 (t, J = 7.1, 1H, H-6), 6.25 (d, J = 8.1 Hz, 1H, H-8), 6.09 (d, J = 3.4 Hz, 1H, NH), 5.22 (m, 1H, H-2), 4.54 (d, J = 17.2 Hz, 1H, CHH-4) and 4.36 (d, J = 17.2 Hz, 1H, CHH-4), 2.25 (s, 3H, CH3-4′) and 1.22 (d, 3H, J = 6.3 Hz, CH3-2). 1H NMR (250 MHz, CDCl3): δ/ppm 7.59 (d, J = 8.3 Hz, 2H, 2 × H-2′), 7.06 (d, J = 8.3 Hz, 2H, 2 × H-3′), 6.90 (t, 1H, H-7), 6.86 (d, 1H, H-5), 6.67 (dt, J = 7.5 and 1.1 Hz, 1H, H-6), 6.29 (d, J = 8.1 Hz, 1H, H-8), 5.36 (dq, J = 6.4 and 1.0 Hz, 1H, H-2), 4.70 (d, J = 17.4 Hz, 1H, CH2-4), 4.47 (d, J = 17.4 Hz, 1H, CH2-4), 2.29 (s, 3H, CH3) and 1.40 (d, J = 6.4 Hz, 3H, CH3). 13C NMR (62.5 MHz, CDCl3): δ/ppm 143.2 (C4′), 139.7 (C8a), 136.2 (C1′), 129.0 (2 × C3′), 127.6 (C5), 127.3 (2 × C2′), 126.4 (C7), 118.8 (C6), 116.9 (C4a), 116.4 (C8), 61.4 (CH), 41.8 (CH2), 21.5 (CH3) and 21.4 (CH3). IR (KBr, cm−1): 3387(s) ν(NH) cm−1, 1326(s) νas(SO2), 1158(vs) νs(SO2). MS (ESI) m/z = 325 (MNa+). HRMS calcd for C16H18N2NaO2S (MNa+): 325.0981; found, 325.0967. Elemental analysis (found): C 63.5, H 5.8, N 9.1; S, 10.5%. Calc. for C16H18N2O2S: C, 63.6; H, 6.0; N, 9.3; S, 10.6%.




http://pubs.rsc.org/en/content/articlehtml/2016/RA/C6RA20886J


//////////////

Thursday 28 September 2017

Development of a General Protocol To Prepare 2H-1,3-Benzoxazine Derivatives

Figure
2H-1,3-Benzoxazine natural products and related bioactive molecules.

4-(2-Bromo-5-chlorobenzyl)-7-chloro-2-phenyl-2H-benzo[e][1,3]oxazine 2 as a light-yellow solid (82% yield).
1H NMR (500 MHz, CDCl3): δ (ppm) 7.55–7.52 (m, 3H), 7.42–7.34 (m, 3H), 7.30 (d, 1H, J = 3.5 Hz,) 7.29 (s, 1H), 7.12 (dd, 1H, J = 8.5 Hz, 2.5 Hz), 6.95–6.91 (m, 2H), 6.57 (1H, s), 4.16 (ABq, 2H, ΔδAB = 0.05, JAB = 16.5 Hz).
13C NMR (125 MHz, CDCl3): δ (ppm) 161.5, 155.8, 139.2, 138.9, 138.1, 133.8, 133.5, 130.6, 128.8, 128.7, 128.5, 127.0, 126.3, 122.6, 121.9, 117.3, 116.2, 88.9, 40.8.
HRMS TOF MS (m/z): [M + H]+ calcd for [C21H14BrCl2NO H] 445.9709; found 445.9713.
FTIR(neat): 3060, 1633, 1596, 1454, 1364, 1344 cm–1.
Spectroscopic data for 2 were identical to those reported in the literature.(4)
LiH.BelykK. M.YinJ.ChenQ.HydeA.JiY.OliverS.TudgeM.CampeauL.-C.CamposK. R. J. Am. Chem. Soc. 2015137,13728– 13731 DOI: 10.1021/jacs.5b05934

Development of a General Protocol To Prepare 2H-1,3-Benzoxazine Derivatives

 Department of Process Research and Development, MSD R&D (China) Co., Ltd., Building 21 Rongda Road, Wangjing R&D Base, Zhongguancun Electronic Zone West Zone, Beijing 100012, China
 Department of Process Research and Development, Merck Sharp & Dohme, Hertford Road, Hoddesdon, Hertfordshire EN11 9BU, United Kingdom
§ Department of Synthetic Chemistry, Pharmaron Beijing Co., Ltd., 6 Taihe Road BDA, Beijing, 100176, China
 Department of Process Research and Development, Merck Research Laboratories, P.O. Box 2000, Rahway, New Jersey 07065, United States
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.7b00209
Publication Date (Web): August 23, 2017
Copyright © 2017 American Chemical Society
*E-mail: ji_qi@merck.com.
ACS Editors’ Choice – This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.

Abstract

Abstract Image
A practical synthesis and detailed development process of 2H-1,3-benzoxazine derivatives catalyzed by aldimine and trifluoromethanesulfonic acid is described. A broad range of substrates with diverse steric and electronic properties were explored. Aliphatic/aromatic/heteroaromatic substrates all proceed well under conditions which have been optimized into a robust, scalable process.