Tungsten hexachloride (WCl6) as an efficient catalyst for chemoselective dithioacetalization of carbonyl compounds and transthioacetalization of acetals
The wide use of 1,3-dithianes and 1,3-dithiolanes as protecting groups for the carbonyl functionality,1 as nucleophilic acyl anion equivalents,2 and as masked methylene functions3 demands an intense search for new synthetic methods of these compounds. Dithioacetals are usually prepared by the acid catalyzed condensation of carbonyl compounds with thiols.1 Several types of acid catalysts used for this purpose including BF3.Et2O,4 ZnCl2,5 LnCl3,6 ...
