The reaction of acetone with hydrogen sulfide

A crystalline compound (“tetrathiopentone”, C15H28S4) has been isolated in high yield from the reaction of acetone with hydrogen sulfide in an acidic medium. Its structure was established as, 2,2,4,4,8,8,10,10-octamethyl-3,5,7,9-tetrathiaspiro[5,5]undecane (I).