A Brønsted acid catalysed enantioselective Biginelli reaction

A Bronsted acid catalysed enantioselective Biginelli reaction

Green Chem., 2017, Advance Article
DOI: 10.1039/C6GC03274E, Paper
Margherita Barbero, Silvano Cadamuro, Stefano Dughera
A chiral derivative of 1,2-benzenedisulfonimide, namely (-)-4,5-dimethyl-3,6-bis(o-tolyl)-1,2-benzenedisulfonimide is herein proven to be an efficient chiral catalyst in a one pot three-component Biginelli reaction.

A Brønsted acid catalysed enantioselective Biginelli reaction

*Corresponding authors
aDipartimento di Chimica, Università di Torino, C.so Massimo d’Azeglio 48, 10125 Torino, Italy
E-mail: stefano.dughera@unito.it
Green Chem., 2017, Advance Article

DOI: 10.1039/C6GC03274E

A chiral derivative of 1,2-benzenedisulfonimide, namely (−)-4,5-dimethyl-3,6-bis(o-tolyl)-1,2-benzenedisulfonimide is herein proven to be an efficient chiral catalyst in a one pot three-component Biginelli reaction. In fact the yields of the target dihydropyrimidines were very high (25 examples; average 91%) and enantiomeric excesses were always excellent (14 examples; average 97%). Ultimately, we herein propose a procedure that displays a number of benefits and advantages including the total absence of solvents, mild reaction conditions, relatively short reaction times and stoichiometric reagent ratios. Target dihydropyrimidines are obtained in adequate purity, making further chromatographic purification unnecessary. Moreover, the chiral catalyst was easily recovered from the reaction mixture and reused, without the loss of catalytic activity.

(R)-(-)-Ethyl 6-methyl-4-phenyl-2-thioxo-3,4-dihydropyrimidine-5-carboxylate (5a): pale grey solid (135 mg, 98% yield); mp 201–202 °C ( from EtOH; lit17 200–202 °C). 96.4% Ee (GC connected to a J&W Scientific Cyclosil-B column; stationary phase: 30% heptakis (2,3-di-Omethyl-6-O-t-butyldimethylsilyl)-β-cyclodextrin in DB-1701), tR= 12.11 min (major), tR= 12.54 min (minor); [a]D -65.4 (c 0.1 in MeOH).

1H NMR (200 MHz, DMSO-d6): δ = 10.24 (br s, 1H), 9.55 (br s, 1H), 7.31–7.12 (m, 5H), 5.09 (d, J = 3.9 Hz, 1H), 3.92 (q, J = 7.0 Hz, 2H), 2.21 (s, 3H), 1.01 (t, J = 7.0 Hz, 3H);

13C NMR (50 MHz, DMSO-d6): δ = 174.9, 165.8, 145.7, 129.3, 128.3, 127.0, 101.3, 60.2, 54.7, 17.8, 14.7.

MS (m/z, EI): 276 [M+ ] (45), 247 (40), 199 (100). IR (neat) ν (cm−1): 3311 (NH), 3112 (NH), 1665 (CO), 1195 (CS).

USES

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////////////Bronsted acid,  catalysed, enantioselective, Biginelli reaction

Highly chemoselective reduction of nitroarenes over non-noble metal nickel-molybdenum oxide catalysts

Highly chemoselective reduction of nitroarenes over non-noble metal nickel-molybdenum oxide catalysts

Green Chem., 2017, 19,809-815
DOI: 10.1039/C6GC03141B, Paper
Haigen Huang, Xueguang Wang, Xu Li, Chenju Chen, Xiujing Zou, Weizhong Ding, Xionggang Lu
A non-noble Ni-MoO3/CN@SBA-15 catalyst exhibits unprecedented catalytic activity and chemoselectivity for the reduction of nitroarenes to anilines in ethanol with hydrazine hydrate.

Highly chemoselective reduction of nitroarenes over non-noble metal nickel-molybdenum oxide catalysts

Haigen Huang,a   Xueguang Wang,*ab   Xu Li,a  Chenju Chen,b   Xiujing Zou,b   Weizhong Dingab and  Xionggang Lu*ab  
*Corresponding authors
aState Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072, China
E-mail: wxg228@shu.edu.cn, luxg@shu.edu.cn
bShanghai Key Laboratory of Advanced Ferrometallurgy, Shanghai University, China
Green Chem., 2017,19, 809-815

DOI: 10.1039/C6GC03141B

The chemoselective reduction of nitroarenes is an important transformation for the production of arylamines, which are the primary intermediates in the synthesis of pharmaceuticals, agrochemicals and dyes.
Heterogeneous non-noble metal nickel-molybdenum oxide catalysts supported on ordered mesoporous silica SBA-15 (Ni-MoO3/CN@SBA-15) were prepared for the first time by treating SBA-15-supported nickel-molybdenum oxide materials with 1,10-phenanthroline, and exhibited unprecedented catalytic activity and chemoselectivity for the reduction of various substituted nitroarenes to the corresponding aromatic amines in ethanol with hydrazine hydrate as a hydrogen donor under mild conditions owing to the synergistic effect of metal Ni and MoO3 species, affording excellent yields of >99% within very short reaction periods (≤60 min).
The Ni-MoO3/CN@SBA-15 catalysts were highly stable and could easily be recovered by simple filtration or by an external magnetic field for at least ten recycling reactions without any observable loss of catalytic performance or leaching of metal components.
//////////

Synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions at room temperature

Synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions at room temperature

Green Chem., 2017, Advance Article
DOI: 10.1039/C6GC03494B, Paper
Zheng Fang, Wen-Li Hu, De-Yong Liu, Chu-Yi Yu, Xiang-Guo Hu
A procedure for the synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions has been developed.

Synthesis of tetrazines from gem-difluoroalkenes under aerobic conditions at room temperature

Zheng Fang,a   Wen-Li Hu,a   De-Yong Liu,a  Chu-Yi Yuab and   Xiang-Guo Hu*a  
*Corresponding authors
aNational Engineering Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, P. R. China
E-mail: huxiangg@iccas.ac.cn
bBeijing National Laboratory for Molecular Science (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
Green Chem., 2017, Advance Article

DOI: 10.1039/C6GC03494B, http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C6GC03494B?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

An efficient and green procedure for the synthesis of tetrazines has been developed based on an old chemistry reported by Carboni in 1958. Both symmetric and asymmetric 3,6-disubstituted 1,2,4,5-tetrazines can be obtained in moderate to high yields from the corresponding gem-difluoroalkenes under aerobic conditions at room temperature. This work represents a rare example that ambient air is utilized as an oxidant for the synthesis of tetrazines.
Synthesis of symmetric 3,6-dialkyl-1,2,4,5−tetrazine(3a−3h)
To a solution of 1,1−difluoroalkenes (1a, 50 mg, 0.27 mmol) in N,N-dimethylformide (DMF,5 mL) was added hydrazine (80%, 35 mg, 1.35 mmol). After stirring at room temperature for 4−6 hours, saturated ammonium chloride (20 mL) was added and the reaction mixture was extracted with dichloromethane (10 mL×3). The organic layer was combined, dried with anhydrous sodium sulfate. The solvent was concentrated and the crude product was dissolved in a suspension of Ethyl Acetate(5 mL) and 10% potassium carbonate solution(wt%, 5 mL) and stirred at room temperature for 24h under air atomerspere until the organic layer turned into amaranth obviously. The organic layer was collected, dried with anhydrous sodium sulfate. The crude product was purified by flash column chromatography[silica gel(#100–200), toluene] to afford the pure 1,2,4,5−tetrazines(3a−3h).
3,6−bis([1,1’−biphenyl]−4−ylmethyl)−1,2,4,5−tetra zine (3a).
str1
(41 mg, 83%).
purple solid; m.p. 200−202°C;
IR(KBr) nmax/cm−1 2924, 2850, 1488, 1451, 1432, 1388, 851, 750;
1 H NMR (400 MHz, CDCl3) 7.55−7.33 (m, 18H), 4.65 (s, 4H).
13C NMR (100 MHz, CDCl3) δ 169.2, 140.6, 140.4, 134.8, 129.7, 128.8, 127.6, 127.4, 127.1, 40.9;
HRMS (ESI): calcd. for C28H22N4 [M+H]+ 415.19172, found 415.19124.

///////tetrazines,  gem-difluoroalkenes, aerobic conditions, room temperature

Photobiocatalytic alcohol oxidation using LED light sources

Green Chemistry International


Photobiocatalytic alcohol oxidation using LED light sources

Oxidative lactonization of meso-3-methyl-1,5-pentanediol to (S)-4-methyltetrahydro-2H-pyran-2-one using horse liver alcohol dehydrogenase (HLADH) and photocatalytic, aerobic regeneration of NAD+.

Green Chem., 2017, 19,376-379
DOI: 10.1039/C6GC02008A, Communication
Open Access Open Access
Creative Commons Licence  This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
M. Rauch, S. Schmidt, I. W. C. E. Arends, K. Oppelt, S. Kara, F. Hollmann
The photocatalytic oxidation of NADH using a flavin photocatalyst and a simple blue LED light source is reported.

Photobiocatalytic alcohol oxidation using LED light sources

M. Rauch,a  S. Schmidt,a  I. W. C. E. Arends,a  K. Oppelt,b  S. Karac and  F. Hollmann*a  
*Corresponding authors
aDepartment of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629HZ Delft, The Netherlands
E-mail: f.hollmann@tudelft.nl
b

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Asymmetric synthesis of (S)-phenylacetylcarbinol – closing a gap in C–C bond formation

Green Chemistry International

Graphical abstract: Asymmetric synthesis of (S)-phenylacetylcarbinol – closing a gap in C–C bond formation

image file: c6gc01803c-f3.tif
Fig. 3 Stereoselectivities of the new ApPDC-variants for the synthesis of (S)-PAC. The different variants were tested as wet cells, crude cell extracts, and purified enzymes. Reaction conditions: wet cells – 20 mM benzaldehyde; 200 mM pyruvate; 50 mM KPi-buffer (pH 6.5), 2.5 mM MgSO4; 0.1 mM ThDP; 20 °C; 800 rpm, 800 μL reaction volume in 1.5 mL closed glass vials, whole cell catalyst concentration of 50 mg mL−1. Crude cell extract – 20 mM benzaldehyde; 200 mM pyruvate; 50 mM KPi-buffer (pH 6.5), 2.5 mM MgSO4; 0.1 mM ThDP; 20 °C; 800 rpm, 500 μL reaction volume in a 96-well sheet; see ESI chapter 2.1.4–2.1.5 for the catalyst concentration. Purified enzyme – 40 mM benzaldehyde; 200 mM pyruvate; 50 mM KPi-buffer with three different pH values, 2.5 mM MgSO4; 0.1 mM ThDP; 22 °C; 800 rpm…

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Endogenous water-triggered and ultrasound accelerated synthesis of 1,5-disubstituted tetrazoles via a solvent and catalyst-free Ugi-azide reaction

 

Endogenous water-triggered and ultrasound accelerated synthesis of 1,5-disubstituted tetrazoles via a solvent and catalyst-free Ugi-azide reaction

Green Chem., 2017, Advance Article
DOI: 10.1039/C6GC03324E, Communication
Shrikant G. Pharande, Alma Rosa Corrales Escobosa, Rocio Gamez-Montano
An ultrasound accelerated, environmentally benign Ugi-azide based method was developed for the synthesis of 1,5-disubstituted tetrazoles under solvent and catalyst-free conditions.

Endogenous water-triggered and ultrasound accelerated synthesis of 1,5-disubstituted tetrazoles via a solvent and catalyst-free Ugi-azide reaction

 *Corresponding authors
aDepartamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta S/N, Col. Noria Alta, Guanajuato, México
E-mail: rociogm@ugto.mx
Green Chem., 2017, Advance Article

DOI: 10.1039/C6GC03324E,  http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C6GC03324E?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

A novel, sustainable, endogenous water-triggered, environmentally friendly, high substrate scope, efficient, solvent-free and catalyst-free Ugi-azide based method for the synthesis of 1,5-disubstituted tetrazoles is described.
Shrikant Pharande

Shrikant Pharande

Doctoral student

Research experience

  • Apr 2014–Jun 2014, Research chemist
    TCG Lifesciences · pune
  • Mar 2012–Dec 2013, project assistant
    CSIR – National Chemical Laboratory, Pune · Organic Chemistry Division (NCL)
N-((1-(tert-butyl)-1H-tetrazol-5-yl)(4-chlorophenyl)methyl)aniline (4a)
Based on GP, 100 mg 4-Chlorobenzaldehyde (0.71 mmol), 0.065 cm3 aniline (0.71 mmol), 0.080 cm3 ter. Butyl isocyanide (0.71 mmol), and 0.093 cm3 TMS-azide (0.71 mmol) were reacted together to afford 237 mg (97%) as a white solid.
Melting range 144-145oC,
Rf = 0.45 (Hexane-AcOEt = 7/3 V/V),
1H NMR (500 MHz, CDCl3) δ 7.34 – 7.29 (m, 4H), 7.18 – 7.13 (m, 2H), 6.79 – 6.75 (m, 1H), 6.65 (d, J = 7.6 Hz, 2H), 6.11 (d, J = 6.2 Hz, 1H), 4.78 (d, J = 5.6 Hz, 1H), 1.71 (s, 9H);
13C NMR (126 MHz, CDCl3) δ 155.03, 145.54, 136.81, 134.71, 129.62, 129.43, 129.19, 119.64, 114.42, 61.95, 53.93, 30.29;
FT-IR (ATR) νmax/cm-1 3330.5, 3052.5, 2940.9, 1603.6, 1284.1;
HRMS (ESI+): m/z calcd. for C18H20ClN5 + 342.1480, found 342.1474
str1
str2

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FOTAGLIPTIN

New Drug Approvals

str1

SCHEMBL2020371.pngstr1

FOTAGLIPTIN

CAS 1312954-58-7

342.37, C17 H19 F N6 O

Benzonitrile, 2-[[3-[(3R)-3-amino-1-piperidinyl]-6-methyl-5-oxo-1,2,4-triazin-4(5H)-yl]methyl]-4-fluoro-

(R)-2-((3-(3-amino-piperidin-1-yl)-6-methyl-5-oxo-1,2,4-piperazine-4(5H)-yl)methyl)-4-fluorobenzonitrile,

BENZOATE 1403496-40-1

(R) 2- Methyl-5-oxo-1,2,4-triazin-4 (5H) -yl) methyl) -4-fluorobenzonitrile (3- benzoate (compound benzoate A), of the formula: the C . 17 the H 19 the FN . 6 O · the C . 7 the H . 6 O 2 , molecular weight: 464.49.

useful as a dipeptidyl peptidase IV (DPPIV) inhibitor for treating diabetes, particularly type 2 diabetes

Dipeptidyl peptidase IV inhibitor,

a DPPIV inhibitor, being developed by Chongqing Fochon, with licensee Shenzhen Salubris Pharmaceuticals, for treating type 2 diabetes mellitus. In January 2017, fotagliptin benzoate was reported to be in phase 1 clinical development. The compound of the present invention was first disclosed in WO2011079778. See WO2015110078 and WO2015110077, claiming crystalline polymorphic form of the DPPIV inhibitor.

  • Originator Chongqing Fochon Pharmaceutical
  • Class Antihyperglycaemics
  • Mechanism of Action CD26 antigen inhibitors
  • Shanghai Fosun Pharma…

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