Abstract
The oxidative cleavage of 2-alkyl-2-(1-hydroxyalkyl)-1, 3-dithianes (1-5) and 2-(1-hydroxyethyl)-2-methyl-1, 3-dithiolane (11) with Pb (OAc)4 gave 3-alkyl-1, 4-dithiepan-2-ones (7a-e) and 1, 4-dithian-2-one (12), respectively, in fairly good yields. Analogously, the treatment of 2-alkylidene-1, 3-dithianes (13a-e) with Pb (OAc)4 resulted in a ring expansion to give 7a-e, whereas the reaction of 2-benzylidene-1, 3-dithiane (13f) with Pb (OAc)4 did not produce the expected ring expansion product, instead giving 2-(α-acetoxybenzylidene)-1, 3-dithiane (8).
