Abstract
Reactions of 2-diazocyclohexanone (7) with thioketones and a 1,3-thiazole-5(4H)-thione in THF at 50-60°C in the presence of 10% LiClO4 proceeded by elimination of N2 and yielded 4,5,6,7-tetrahydro-1,3-benzoxathiole derivatives (13-17). In the case of 2,2,4,4-tetramethylcyclobutane-1,3-dithione (12), a 1:5 mixture of cis- and trans-bisadducts (cis/trans-17) was obtained. Under analogous conditions, no reactions occurred with 5,5-dimethyl-2-diazocyclohexane-1,3-dione (18). Only in the presence of 2% Rh2(OAc)4, 18 reacted with dithione (12) yielding the 1,3-benzoxathiole derivative (19).
Kelmendi, Bashkim