AZO BRIDGES FROM AZINES .15. OXYGENATION OF UNSATURATED CYCLIC AZO-COMPOUNDS WITH PERACIDS

Azo bridges in compounds 3, 6, 11, 16, 20 and 22 are chemospecifically oxidized with MCPBA to the corresponding azoxy derivatives 4, 7, 12, 17, 21, and 23 in the presence of one or two (20, 22) double bonds eve n if these are located in a close parallel position to the azo bridge (6, 11, 20, 22). The order of reactivity of different olefinic moietie s towards MCPBA was found to be bicycloheptene > bicyclooctene, cyclop entene. Thus, epoxy/azoxides 5, 8, 13, 14, and 19 as well as bisepoxy/ azoxides 10 and 15 were obtained. If both the azo and the olefinic bri dge are part of a bicycloheptane system (24) the azo group can be no l onger oxidized chemospecifically (25 + 26).