[CONTRIBUTION FROM THE CHEMICAL LABORATORY OF HARVARD ... UNIVERSITY] UNSATURATED 1,4-DIKETONES I. HALOGEN DERIVATIVES OF DIBENZOYL-ETHYLENE AND RELATED SUBSTANCES BY JAMES B. CONANT AND ROBERT E. LUTZ RECBIVBD JANUARY 27, 1925 PUBLISHED MARCH 6,1925 ... The recently developed synthesis of dibenzoyl-ethylene from fumaryl chloride and benzene by the Friedel-Crafts reaction1 makes readily accessible unsaturated 1,4- ...