부산대학교 도서관

1,3-Dialkyl-4,5-dimethylimidazole-2-thiones 1a, 1b and acyclic N,N,N’,N’ -tetramethylthiourea 3 react with sulfuryl dichloride to yield a new type of sulfur ylides, 1,3-dialkyl-4,5-dimethylimidazol-2-ylidenesulfonium dichloromethylides 2a, 2b and bis(dimethylamino)methylenesulfonium dichloromethylide 4 , respectively. The reaction of 2a and 4 with acetylacetone results in the formation of thione S-ylides 5 and 6 , whereas the reaction with dimethyl(trimethylsilyl)amine leads to the formation of S -dimethylaminothiouronium chlorides 8a , 8b , and 9 , respectively. Anion metathesis of 8a, 8b , and 9 with NaX affords compounds 10a?–?10c, 11a , and 11b (X?=?BPh4, BF4). Compounds 8a and 9 are involved in a [3?+?2] cycloaddition reaction when treated with dimethyl acetylenedicarboxylate, resulting in salt-like derivatives of isothiazolines 12?–?15 . These new compounds have been characterized by spectrometric and elemental analyses, and the solid-state structure of compound 10a has also been determined by single-crystal X-ray structural analysis. [ABSTRACT FROM AUTHOR]