Photochemical synthesis of oxime acetates derivatives of 1-carbaldehydobicyclo[n.1.0]alkanes by the aza-di-π-methane rearrangement.

Abstract

The first photochemical synthesis of some 1-carbaldehydobicyclo[n.1.0]alkane oxime acetates has been achieved by the aza-di-π-methane (ADPM) rearrangement of oxime acetates of 2-(cyclopent-1-enyl)- and 2-(cyclohex-1-enyl)-2-methylpropanals. Further increase in ring-size affects adversely the reaction and the oxime acetate of 2-(cyclohept-1-enyl)-2-methylpropanal is unreactive by the ADPM path. The low efficiency of rearrangement of 2-(cyclohex-1-enyl)-2-methylpropanal can be overcome by incorporation of a benzo substituent and this compound, 2-(2-[3,4-dihydronaphthalenyl])-2-methylpropanal, undergoes the ADPM rearrangement efficiently.