Untersuchungen an ß-Sultonen, 4. Mitt. Zur Reaktion von vicinalen Polycarbonylverbindungen mit Alkansulfonylhalogeniden und Triethylamin2,3), Teil 1

Investigations of ß-Sultones, IV:¹⁾ On the Reaction of Vicinal Polycarbonyl Compounds with Alkanesulfonyl Halides and Triethylamine^2,3), Part 1 The vicinal tricarbonyl compounds 1 and 5 react with alkanesulfonyl halides and triethylamine via the postulated β-sultones 3 or 6 to yield 4a or mixtures of the 2-chloro-1.3-dioxoindan-2-yl alkanesulfonates 7 and the 1,3,4-dioxathiane-2,6-dispiro compounds 8 . Reactions of 7 and 8 with nitrogenous bases afford the 2-(aminomethylidene)-1,3-indanediones 20 among other compounds. The chlorine in compounds 7 is difficult to replace by nucleophiles. With nitrogenous bases only exchange of the sulfonate base occurs. Thioureas on the other hand yield the isothioureas 9 .