Abstract:

1-(1, 3-dithian-2-ylidene)propan-2-one 1f, which is odorless and steady white crystal at room temperature, was prepared readily in 86% yield via decarbonylation of 3- (1, 3-Dithian-2-ylidene)-pentane-2,4-Dione 1b under acidic condition. Thioacetalization reactions of odorless 1-(1, 3-dithian-2-ylidene)propan-2-one as efficient 1, 3-propandithiol equivalent with selected aldehydes and ketones were carried out at room and reflux temperature in the present of MeCOCl in MeOH, and 1, 3-dithiane derivatives were obtained in excellent yield (86-99%). Compared with reported 1a-e, 1f is regarded as optimal 1, 3- propandithiol equivalent in thioacetalization reaction.

Key words: 1-(1, 3-dithian-2-ylidene)propan-2-one, thiol equivalents, thioacetalization reaction.