A two-step synthesis of allylic syn 1,3-diols via an intramolecular oxa-Michael reaction followed by a modified Julia olefination
作者:Raphaël Oriez、Joëlle Prunet
DOI:10.1016/j.tetlet.2009.10.139
日期:2010.1
of allylic syn 1,3-diols is developed. An intramolecular oxa-Michael reaction onto vinyl heteroaromatic sulfones allows the diastereoselective formation of 1-sulfonyl 2,4-diols protected as benzylideneacetals. These sulfones are then engaged in a modified Julia olefination to furnish the olefins contiguous to the benzylideneacetal ring with good E/Z selectivity.
We have developed a regioselective allylation and a regio- and diastereoselective crotylation of aldehydes with pyridin-2-yl sulfides. In the process, we have also optimized the diastereoselectivity of the addition of crotyl phenyl sulfide to aldehydes.