<i>N</i>‐Methylmorpholine <i>N</i>‐Oxide: A Rare Nonmetallic Catalyst for the Most Efficient Silylcyanation of Aldehydes
作者:Sung Soo Kim、Gurusamy Rajagopal、Dong Won Kim、Dae Ho Song
DOI:10.1081/scc-200026652
日期:2004.1.1
An efficient method of addition of trimethylsilyl cyanide (TMSCN) to aldehydes by employing N-methylmorpholine N-oxide (NMO) alone as the catalyst has been described. Most of aromatic, aliphatic, cyclic, and heterocyclic aldehydes have been converted into their corresponding trimethylsilyl ethers in excellent yield within 10-min period. The mechanism of silylcyanation reaction has been also described.
Enzymatic preparation of optically active cyanohydrin acetates
作者:Andreas van Almsick、Joachim Buddrus、Petra Hönicke-Schmidt、Kurt Laumen、Manfred P. Schneider
DOI:10.1039/c39890001391
日期:——
A series of cyanohydrinacetates (1)–(47) of widely varying structures, potential chiral building blocks for numerous synthetic applications, has been prepared in good chemical and often high optical yields by enzymatic hydrolysis of their racemic acetates in the presence of an ester hydrolase from Pseudomonas sp.
Niobium Fluoride (NbF<sub>5</sub>): A Highly Efficient Catalyst for Solvent-Free Cyanosilylation of Aldehydes
作者:Sung Kim、Gurusamy Rajagopal
DOI:10.1055/s-2006-958942
日期:2007.1
An efficient method for the addition of trimethylsilylcyanide (TMSCN) to aldehydes using dispersed NbF5 as the catalyst is described. Cyano transfer from TMSCN to aldehydes occurs within 10 minutes at room temperature in the presence of 0.5 mol% of NbF5 under solvent-free conditions giving cyanohydrins in excellent yields of over 95%. These conditions are extremely mild, simple and tolerate various functional groups.