The Use of Grignard Reagents in the Synthesis of Carbohydrates. II. The Cleavage of Acetal Protecting Groups in Sugar Derivatives
作者:Masajiro Kawana、Sakae Emoto
DOI:10.1246/bcsj.53.230
日期:1980.1
The selective reaction of acetal protecting groups in sugars with Grignard reagents is described. The treatment of 1,2:5,6-di-O-cyclohexylidene-α-D-glucofuranose (1) with methylmagnesium iodide in benzene-ether at about 85 °C gave 1,2-O-cyclohexylidene-6-O-(1-methylcyclohexyl)-α-D-glucofuranose. When isopropylmagnesium iodide or t-butylmagnesium bromide was used instead of methylmagnesium iodide, 1
描述了糖中缩醛保护基团与格氏试剂的选择性反应。1,2:5,6-di-O-cyclohexylidene-α-D-glucofuranose (1) 在苯醚中用甲基碘化镁在约 85 °C 下处理得到 1,2-O-cyclohexylidene-6-O- (1-甲基环己基)-α-D-呋喃葡萄糖。当使用异丙基碘化镁或叔丁基溴化镁代替甲基碘化镁时,1 得到 1,2-O-cyclohexylidene-6-O-(cyclohex-1-enyl)-α-D-glucofuranose 和相应的 6-O-cyclohexyl衍生物。还描述了使用格氏试剂选择性裂解一些其他糖类中的缩醛保护基团。