Treatment of 3, 6-dibenzoyl-l, 8-diphenyl-4, 5dithiat-l, &octanedione (11) with potassium ethoxide in ethanol provides 3, 5dibenzoyl-l, 7diphenyl4thia-l, 7-heptanedione (IV) and potassium lI4diphenyl-2-butene-l, 4-dione-2-mercaptide (VII) as the major products. A