119718-89-7Relevant academic research and scientific papers
Combination of the Lipase-Catalysed Resolution with Mitsunobu Esterification in One Pot
Vaenttinen, Eero,Kanerva, Liisa T.
, p. 1779 - 1786 (1995)
A chemo-enzymatic method for the preparation of homochiral esters of 14 secondary alcohols with 100percent theoretical yields is described in one pot through two steps: the lipase-catalysed kinetic resolution followed by the Mitsunobu esterification of the free alcohol enantiomer in situ in the resolution mixture.Mathematical equations which link the enzymatic and chemical steps were derived, resulting in an enantioconvergent synthetic tool for the preparation of chiral intermediates.
Asymmetric Cyanosilylation of Aldehydes by a Lewis Acid/Base Synergistic Catalyst of Chiral Metal Clusters
Huang, Kai-Xin,Kong, Xiang-Jian,Li, Jun-Ping,Long, La-Sheng,Weng, Zhen-Zhang,Xie, Jing,Zheng, Lan-Sun
, p. 4121 - 4129 (2022/03/09)
Metal clusters with well-defined crystal structures are extremely useful for studying the synergistic catalytic effects and associated catalytic mechanisms. In this study, two pairs of chiral lanthanide-transition metal clusters (R)/(S)-Co3Ln2(Ln = Tb or Dy) were synthesized using Schiff-base ligands [(R)- or (S)-H3L] with multiple Lewis base sites (O sites). The as-prepared (R)/(S)-Co3Ln2chiral metal clusters exhibited good catalytic functionality in the asymmetric synthesis of chiral cyanohydrins, with high conversions of up to 99% and medium-to-high enantiomeric excess values of up to 78%. The catalysis process followed a mechanism in which the bifunctional metal clusters of (R)/(S)-Co3Ln2, containing Lewis acid sites and Lewis base sites, simultaneously activated the aldehydes and trimethylsilyl cyanide, respectively. Consequently, synergistic catalysis was realized. The enantioselectivity of the different aldehydes and stereochemical configuration of the resulting products are attributed to the formation of a steric chiral pocket via the external chiral ligands on the clusters. In addition, heterogeneous asymmetric cyanosilylation using (R)/(S)-Co3Ln2chiral metal clusters achieved high chemoselectivity and regioselectivity under mild conditions.
Palladium-catalyzed C-H activation of simple arenes and cascade reaction with nitriles: access to 2,4,5-trisubstituted oxazoles
Dai, Ling,Yu, Shuling,Shao, Yinlin,Li, Renhao,Chen, Zhongyan,Lv, Ningning,Chen, Jiuxi
supporting information, p. 1376 - 1379 (2021/02/22)
An efficient and straightforward protocol for the assembly of the pharmaceutically and biologically valuable oxazole skeleton is achieved for the first time from readily available simple arenes and functionalized aliphatic nitriles. This transformation in
Synthesis of Imidazoles and Oxazoles via a Palladium-Catalyzed Decarboxylative Addition/Cyclization Reaction Sequence of Aromatic Carboxylic Acids with Functionalized Aliphatic Nitriles
Dai, Ling,Yu, Shuling,Lv, Ningning,Ye, Xuanzeng,Shao, Yinlin,Chen, Zhongyan,Chen, Jiuxi
supporting information, p. 5664 - 5668 (2021/08/01)
We herein report an efficient approach for the assembly of multiply substituted imidazoles and oxazoles in a single-step manner. These transformations are based on a decarboxylation addition and annulation of readily accessible aromatic carboxylic acids a
Constructing a triangular metallacycle with salen-Al and its application to a catalytic cyanosilylation reaction
Li, Bo,Li, Yang,Qiu, Huayu,Xu, Jun,Yin, Shouchun,Zhang, Jinjin,Zhang, Pengfei,Zhang, Yueyue
supporting information, p. 10399 - 10402 (2021/10/12)
A triangular metallosalen-based metallacycle was constructed in quantitative yield by the self-assembly of a 180° bis(pyridyl)salen-Al complex and a 60° diplatinum(ii) acceptor in a 1?:?1 stoichiometric ratio. This metallacycle was then successfully used to cyanosilylate a wide range of benzaldehydes with trimethylsilyl cyanide.
A High-Throughput Screening Method for the Directed Evolution of Hydroxynitrile Lyase towards Cyanohydrin Synthesis
Zheng, Yu-Cong,Ding, Liang-Yi,Jia, Qiao,Lin, Zuming,Hong, Ran,Yu, Hui-Lei,Xu, Jian-He
, p. 996 - 1000 (2021/01/15)
Chiral cyanohydrins are useful intermediates in the pharmaceutical and agricultural industries. In nature, hydroxynitrile lyases (HNLs) are a kind of elegant tool for enantioselective hydrocyanation of carbonyl compounds. However, currently available methods for demonstrating hydrocyanation are still stalled at precise, but low-throughput, GC or HPLC analyses. Herein, we report a chromogenic high-throughput screening (HTS) method that is feasible for the cyanohydrin synthesis reaction. This method was highly anti-interference and sensitive, and could be used to directly profile the substrate scope of HNLs either in cell-free extract or fermentation clear broth. This HTS method was also validated by generating new variants of PcHNL5 that presented higher catalytic efficiency and stronger acidic tolerance in variant libraries.
Divergent Palladium-Catalyzed Tandem Reaction of Cyanomethyl Benzoates with Arylboronic Acids: Synthesis of Oxazoles and Isocoumarins
Chen, Jiuxi,Chen, Zhongyan,Dai, Ling,Shao, Yinlin,Xiong, Wenzhang,Xu, Tong,Yu, Shuling
supporting information, (2020/04/15)
A palladium-catalyzed tandem reaction of cyanomethyl benzoates with arylboronic acids has been achieved. Substitution at the 2-position of cyanomethyl benzoates was found to be crucial for the selective synthesis of oxazoles and isocoumarins. Cyanomethyl
Synthesis of 2,4,5-Trisubstituted Oxazoles via Pd-Catalyzed C-H Addition to Nitriles/Cyclization Sequences
Zhang, Di,Song, Hao,Cheng, Na,Liao, Wei-Wei
supporting information, p. 2745 - 2749 (2019/04/30)
A practical and flexible intermolecular protocol for the diverse synthesis of trisubstituted oxazole derivatives via a Pd-catalyzed direct C-H addition of electronic-rich heteroarenes to O-acyl cyanohydrins bearing an α-hydrogen/cyclization sequence is described. A wide range of trisubstituted oxazoles can be prepared from readily available starting materials in good to high yields with high efficiency under redox neutral reaction conditions.
Catalytic Transfer Hydration of Cyanohydrins to α-Hydroxyamides
Kanda, Tomoya,Naraoka, Asuka,Naka, Hiroshi
supporting information, p. 825 - 830 (2019/01/14)
We report the palladium(II)-catalyzed transfer hydration of cyanohydrins to α-hydroxyamides by using carboxamides as water donors. This method enables selective hydration of various aldehyde- and ketone-derived cyanohydrins to afford α-mono- and α,α-disubstituted-α-hydroxyamides, respectively, under mild conditions (50 °C, 10 min). The direct conversion of fenofibrate, a drug bearing a benzophenone moiety, into a functionalized α,α-diaryl-α-hydroxyamide was achieved by means of a hydrocyanation-transfer hydration sequence. Preliminary kinetic studies and the synthesis of a site-specifically 18O-labeled α-hydroxyamide demonstrated the carbonyl oxygen transfer from the carboxamide reagent into the α-hydroxyamide product.
Supported Ionic Liquid-Like Phases (SILLPs) as Immobilised Catalysts for the Multistep and Multicatalytic Continuous Flow Synthesis of Chiral Cyanohydrins
Peris, Edgar,Porcar, Raúl,Burguete, María Isabel,García-Verdugo, Eduardo,Luis, Santiago V.
, p. 1955 - 1962 (2019/03/13)
Supported Ionic Liquid-Like Phases have been found to be efficient organocatalysts for the synthesis of cyanohydrin esters under solvent-free conditions by an “electrophile-nucleophile dual activation” based on hydrogen bond formation. The combination of
