system of antimonypentachloride, chlorotrimethylsilane and tin(II) iodide, α-substituted cyclic ethers are stereoselectively prepared from lactones by successive treatment with 1-(t-butyldimethylsiloxy)-1-ethoxyethene and silyl nucleophiles such as triethylsilane, allyltrimethylsilane and trimethylsilyl cyanide. These catalysts also promote the reaction of γ-, δ-, and e-trimethylsiloxy carbonyl compounds
Synthesis of Aliphatic Polyester by Insertion of Glycols into Polyanhydrides Using Lipase Catalyst
作者:Hiroshi Uyama、Satoshi Wada、Shiro Kobayashi
DOI:10.1246/cl.1999.893
日期:1999.9
Polyester synthesis was carried out by insertion-dehydration of glycols into polyanhydrides using Candida antarctica lipase as catalyst. The insertion of 1,8-octanediol into poly(azelaic anhydride) took place under mild reaction conditions to give the corresponding polyester with molecular weight of several thousands.