Selective cleavage of acetals with ZnBr2 in dichloromethane
摘要:
A selective cleavage of acetals of 1,2- and 1,3-diols has been achieved under mild conditions using ZnBr2 in dichloromethane at room temperature. Acetal types cleavable by this procedure include benzylidene, isopropylidene and cyclohexylidene acetals. This method is compatible with several other types of hydroxyl protecting groups such as Bn, Bz, TBDPS, TIPS and TBDMS. (c) 2005 Published by Elsevier Ltd.
Erbium(III) trifluoromethane sulfonate is proposed as a very gentle Lewis acid catalyst in a MW-assisted chemoselective method for the cleavage of isopropylideneacetals in awkward substrates by using pure water as the solvent.
Selective cleavage of acetals with ZnBr2 in dichloromethane
作者:Celia Ribes、Eva Falomir、Juan Murga
DOI:10.1016/j.tet.2005.10.064
日期:2006.2
A selective cleavage of acetals of 1,2- and 1,3-diols has been achieved under mild conditions using ZnBr2 in dichloromethane at room temperature. Acetal types cleavable by this procedure include benzylidene, isopropylidene and cyclohexylidene acetals. This method is compatible with several other types of hydroxyl protecting groups such as Bn, Bz, TBDPS, TIPS and TBDMS. (c) 2005 Published by Elsevier Ltd.