Reactions of Chlorosulfanyl Derivatives of Cyclobutanones with Different Nucleophiles

Abstract

The reactions of 3-chloro-3-(chlorosulfanyl)-2,2,4,4-tetramethylcyclobutan-1-one (2) with N, O, S, and P nucleophiles occur by substitution of Cl at the S-atom. Whereas, in the cases of secondary amines, alkanols, phenols, thiols, thiophenols, and di- and trialkyl phosphates, the initially formed substitution products were obtained, the corresponding products with allyl and propargyl alcohols undergo a [2,3]-sigmatropic rearrangement to give allyl and allenyl sulfoxides, respectively. Analogous substitution reactions were observed when 3-chloro-3-(chlorodisulfanyl)-2,2,4,4-tetramethylcyclobutan-1-one (3) was treated with N, O, and S nucleophiles. The reaction of 3 with Et3P led to an unexpected product via cleavage of the S S bond (cf. Scheme 13). In the reactions of 2 with primary amines and H2O, the substitution products react further via elimination of HCl to yield the corresponding thiocarbonyl S-imides and the thiocarbonyl S-oxide, respectively. Whereas the latter could be isolated, the former were not stable but could be intercepted by MeOH (Scheme 4) or adamantanethione (Scheme 5). The structures of some of the substitution products were established by X-ray crystallography