4815-10-5Relevant articles and documents
Synthesis of a new chiral cyclic o-hydroxynaphthylphosphonodiamide and its application as ligand catalyst in asymmetric silylcyanation of aromatic aldehydes
He, Ke,Zhou, Zhenghong,Wang, Lixin,Li, Kangying,Zhao, Guofeng,Zhou, Qilin,Tang, Chuchi
, p. 1521 - 1524 (2004)
A new chiral cyclic o-hydroxynaphthylphosphonodiamide (+)-2 was synthesized starting from (+)-cis-1,2,2-trimethylcyclopentane-1,3-diamine. The absolute configuration of phosphorus atom was determined as S by X-ray diffraction analysis. Excellent enantiose
CO2-Enabled Cyanohydrin Synthesis and Facile Iterative Homologation Reactions**
Juhl, Martin,Petersen, Allan R.,Lee, Ji-Woong
supporting information, p. 228 - 232 (2020/11/30)
Thermodynamic and kinetic control of a chemical process is the key to access desired products and states. Changes are made when a desired product is not accessible; one may manipulate the reaction with additional reagents, catalysts and/or protecting groups. Here we report the use of carbon dioxide to accelerate cyanohydrin synthesis under neutral conditions with an insoluble cyanide source (KCN) without generating toxic HCN. Under inert atmosphere, the reaction is essentially not operative due to the unfavored equilibrium. The utility of CO2-mediated selective cyanohydrin synthesis was further showcased by broadening Kiliani–Fischer synthesis under neutral conditions. This protocol offers an easy access to a variety of polyols, cyanohydrins, linear alkylnitriles, by simply starting from alkyl- and arylaldehydes, KCN and an atmospheric pressure of CO2.
Hydroxynitrile Lyase Isozymes from Prunus communis: Identification, Characterization and Synthetic Applications
Zheng, Yu-Cong,Xu, Jian-He,Wang, Hui,Lin, Guo-Qiang,Hong, Ran,Yu, Hui-Lei
, p. 1185 - 1193 (2017/04/13)
Biocatalysts originating from Badamu (Prunus communis) have been applied to catalyze the asymmetric synthesis of (R)-4-methylsulfanylmandelonitrile, a key building block of thiamphenicol and florfenicol. Here, four hydroxynitrile lyase (HNL) isozymes from Badamu were cloned and heterologously expressed in Pichia pastoris. The biochemical properties and catalytic performances of these isozymes were comprehensively explored to evaluate their efficiency and selectivity in asymmetric synthesis. Among then, PcHNL5 was identified with outstanding activity and enantioselectivity in asymmetric hydrocyanation. Under the optimized mild biphasic reaction conditions, seventeen prochiral aromatic aldehydes were converted to valuable chiral cyanohydrins with good yields (up to 94%) and excellent optical purities (up to >99.9% ee), which provide a facile access to numerous chiral amino alcohols, hypoglycemic agents, angiotension converting enzyme (ACE) inhibitors and β-blockers. This work therefore underlines the importance of discovering the most potent biocatalyst among a group of isozymes for converting unnatural substrates into value-added products. (Figure presented.).