New Protecting Groups for 1,2-Diols (Boc- and Moc-ethylidene). Cleavage of Acetals with Bases
作者:Xavier Ariza、Anna M. Costa、Montserrat Faja、Oriol Pineda、Jaume Vilarrasa
DOI:10.1021/ol0062289
日期:2000.9.1
[reaction: see text] 1,2-Diols react at rt with alkyl propynoates, in the presence of 4-dimethylaminopyridine, to give cyclic acetals which are quite stable to acid-catalyzed hydrolysis or methanolysis. 1,3-Diols and 1, 4-diols do not form acetals with alkyl propynoates under the same conditions. Deprotection is accomplished with bases (via elimination and addition/elimination steps).