OXIDATION OF ALKENES AND SULFIDES WITH TRANSITION-METAL CATALYSTS

Alkenes and sulfides were oxidized with transition-metal catalysts. Th e oxidant sources include molecular dioxygen, air and iodosylbenzene. The metal ions Mn(III), Fe(III), Co(II) and Ni(II) were used. The cata lysts 1-18 of 1,3-dioxo-, beta-ketoimine- or salen-types were prepared and their efficacy was examined. 1,2-Dihydronaphthalene is most effic iently epoxidized with O-2/Me(2)CHCHO or PhIO in the presence of Mn(II I)-salen catalysts. The Ni(II)-, Co(II)- and Fe(III)-catalysts of eith er beta-ketoimine- or salen-types are useful for epoxidation of styren e, (E)-stilbene and (E)-benzalacetone in the O-2/Me(2)CHCHO system; th ese epoxidations are stereospecific without formation of corresponding diastereomeric epoxides. Oxidation of methyl p-tolyl sulfide with O-2 /M(2)CHCHO is facilitated by the 1,3-dioxo-catalyst Co(II)-1. Monooxid ation is achieved with Me(2)CHCHO in equimolar proportions to give the corresponding sulfoxide, whereas overoxidation is realized with exces s Me(2)CHCHO to give the sulfone. These epoxidation and sulfide oxidat ions all occur at 25 degrees C and are complete in less than a day.