126568-44-3Relevant academic research and scientific papers
Catalytic enantioselective synthesis of tertiary thiols from 5h-thiazol-4-ones and nitroolefins: Bifunctional ureidopeptide-based bronsted base catalysis
Diosdado, Saioa,Etxabe, Julen,Izquierdo, Joseba,Landa, Aitor,Mielgo, Antonia,Olaizola, Iurre,Lopez, Rosa,Palomo, Claudio
, p. 11846 - 11851 (2013)
Fully loaded: The ureidopeptide-based bifunctional Bronsted base 1 efficiently promotes the first direct catalytic Michael reaction of α-mercapto carboxylate surrogates with nitroolefins involving a fully substituted α-carbon atom construction. Copyright
Process Optimisation Studies and Aminonitrile Substrate Evaluation of Rhodococcus erythropolis SET1, A Nitrile Hydrolyzing Bacterium
Coady, Tracey M.,Coffey, Lee,Kinsella, Michael,Lennon, Claire M.,Mareya, Tatenda M.,O'Reilly, Catherine
, p. 512 - 520 (2020/10/02)
A comprehensive series of optimization studies including pH, solvent and temperature were completed on the nitrile hydrolyzing Rhodococcus erythropolis bacterium SET1 with the substrate 3-hydroxybutyronitrile. These identified temperature of 25 °C and pH of 7 as the best conditions to retain enantioselectivity and activity. The effect of the addition of organic solvents to the biotransformation mixture was also determined. The results of the study suggested that SET1 is suitable for use in selected organo-aqueous media at specific ratios only. The functional group tolerance of the isolate with unprotected and protected β-aminonitriles, structural analogues of β-hydroxynitriles was also investigated with disappointingly poor isolated yields and selectivity obtained. The isolate was further evaluated with the α- aminonitrile phenylglycinonitrile generating acid in excellent yield and ee (>99 % (S) – isomer and 50 % yield). A series of pH studies with this substrate indicated pH 7 to be the optimum pH to avoid product and substrate degradation.
Direct Catalytic Asymmetric Addition of Acetonitrile to Aldimines
Saito, Akira,Kumagai, Naoya,Shibasaki, Masakatsu
, p. 8187 - 8190 (2019/09/07)
Despite significant advances in catalytic asymmetric reactions with decent stereocontrol, those using acetonitrile as a pronucleophile are often disregarded due to their low reactivity and insufficient enantioselectivity. Herein we report the resurgence of this reaction in the chemical toolbox with high enantioselectivity (avg. > 95% ee). The combined use of a Ni(II) complex ligated with a chiral biscarbene and tBuOK engages acetonitrile in the catalytic generation of an α-cyanocarbanion and subsequent highly enantioselective addition to aldimines.
Ureidopeptide-based Bronsted bases: Design, synthesis and application to the catalytic enantioselective synthesis of β-amino nitriles from (arylsulfonyl)acetonitriles
Diosdado, Saioa,Lopez, Rosa,Palomo, Claudio
supporting information, p. 6526 - 6531 (2014/06/09)
The addition of cyanoalkyl moieties to imines is a very attractive method for the preparation of β-amino nitriles. We present a highly efficient organocatalytic methodology for the stereoselective synthesis of β-amino nitriles, in which the key to success is the use of ureidopeptide-based Bronsted base catalysts in combination with (arylsulfonyl)acetonitriles as synthetic equivalents of the acetonitrile anion. The method gives access to a variety of β-amino nitriles with good yields and excellent enantioselectivities, and broadens the stereoselective Mannich-type methodologies available for their synthesis. Learning from peptides: A concise route for the catalytic enantioselective synthesis of β-amino nitriles has been achieved by using ureidopeptide-based Bronsted bases as catalysts in the Mannich reaction of N-Boc imines and (arylsulfonyl)acetonitriles (see scheme; Boc=tert-butoxycarbonyl, napht=naphthyl, TMS=trimethylsilyl).
Nitrilase activity screening on structurally diverse substrates: Providing biocatalytic tools for organic synthesis
Vergne-Vaxelaire, Carine,Bordier, Franck,Fossey, Aurelie,Besnard-Gonnet, Marielle,Debard, Adrien,Mariage, Aline,Pellouin, Virginie,Perret, Alain,Petit, Jean-Louis,Stam, Mark,Salanoubat, Marcel,Weissenbach, Jean,De Berardinis, Veronique,Zaparucha, Anne
, p. 1763 - 1779 (2013/07/19)
A high-throughput screening of candidate nitrilases against 25 structurally diverse substrates allowed us to create a wide collection of 125 experimentally validated nitrilases. The enzymes were selected by genomic approach from 700 diverse prokaryotic species and one metagenome as representative of the nitrilase family diversity. The enzymatic screening of this collection expands the biocatalytic toolbox for chemical synthesis by providing a large number of tested nitrilases with their assigned substrates. Three examples illustrate the synthetic potential of our enzyme collection. The syntheses of carboxylic acid building blocks, a β-substituted phenylpropanoic acid, a cyclic γ-keto carboxylic acid and a mononitrile monocarboxylic acid, were achieved from the corresponding nitrile substrates, using three new nitrilases (two from Sphingomonas wittichii and one from Syntrophobacter fumaroxidans). Improvements of nitrilase activities through the optimization of reaction parameters and the preparative biocatalytic synthesis are presented for these three examples. Copyright
Enantioselective biocatalytic hydrolysis of β-aminonitriles to β-amino-amides using Rhodococcus rhodochrous ATCC BAA-870
Chhiba, Varsha,Bode, Moira L.,Mathiba, Kgama,Kwezi, Wendy,Brady, Dean
, p. 68 - 74 (2012/04/10)
A range of β-aminonitriles (3-amino-3-phenylpropanenitrile and derivatives) were synthesised by reaction of various benzonitriles with acetonitrile and subsequent reduction of the resulting acrylonitrile products. These compounds were hydrolysed to the co
Catalytic enantioselective mannich-type reaction with β-phenyl sulfonyl acetonitrile
Gonzalez, Pedro B.,Lopez, Rosa,Palomo, Claudio
supporting information; experimental part, p. 3920 - 3922 (2010/08/06)
Figure presented The organocatalytic addition of β-phenyl sulfonyl acetonitrile 1 to either N-Boc-protected α-amido sulfones or imines allowed the synthesis of enantioenriched α-unsubstituted β-amino nitriles through a Mannich-type reaction.
Catalytic nucleophilic activation of acetonitrile via a cooperative catalysis of cationic Ru complex, DBU, and NaPF6
Kumagai, Naoya,Matsunaga, Shigeki,Shibasaki, Masakatsu
, p. 8598 - 8608 (2008/02/10)
The development of an efficient catalytic system for the direct addition of acetonitrile under mild amine basic conditions is described. A cooperative catalysis of CpRu complex, DBU, and NaPF6 enables chemoselective and catalytic generation of
Kinetic and NMR spectroscopic studies of chiral mixed sodium/lithium amides used for the deprotonation of cyclohexene oxide
Sott, Richard,Granander, Johan,Williamson, Carl,Hilmersson, Goeran
, p. 4785 - 4792 (2007/10/03)
The mixed-metal complex formed from n-butylsodium, n-butyllithium, and a chiral amino ether has been studied by NMR spectroscopy. Three different mixed-metal amides were used as chiral bases for the deprotonation of cyclohexene oxide. The selectivity and initial rate of reaction were compared for sodium-amido ethers, lithium-amido ethers, and mixtures of sodium and lithiumamido ethers in diethyl ether and tetrahydrofuran, respectively. The mixed sodium/lithium amides are more reactive than the single sodium and lithium amides, whereas the stereoselectivities are higher when lithium amides are used. The alkali-metal/γ-amido ethers exhibit both higher initial reaction rates and stereoselectivities than their β-amido ether analogues. NMR spectroscopic studies of mixtures of n-butylsodium (nBuNa), n-butyllithium (nBuLi), and the γ-amino ethers in diethyl ether show the exclusive formation of dimeric mixed-metal amides. In diethyl ether, the lithium atom of the mixed-metal amide is internally coordinated and the sodium atom is exposed to solvent; however, in tetrahydrofuran, both metals are internally coordinated.
Cooperative catalysis of a cationic ruthenium complex, amine base, and Na salt: Catalytic activation of acetonitrile as a nucleophile
Kumagai, Naoya,Matsunaga, Shigeki,Shibasaki, Masakatsu
, p. 13632 - 13633 (2007/10/03)
Cooperative catalysis of a cationic Ru complex, DBU, and NaPF6 is described. An exquisite combination of the catalytic triad enabled catalytic activation of acetonitrile as a nucleophile under mild amine-basic conditions. Addition of in situ-ge
