Reactions related to coenzyme B12 dependent rearrangements: Metal mediated free radical acyl migrations in methyl and cyclopropyl substituted models
作者:Wayne M. Best、David A. Widdowson
DOI:10.1016/s0040-4020(01)89121-3
日期:1989.1
Free radicals generated from the methylmalonylcoenzyme A mutase model substrates (3) and (4) by chromium (II) reduction, or by pyrolysis of the analogous cobaloximes, underwent [1,2]-migration only in the acyl series (R = Ph, Me) and not the critical ester series (R = OEt, SBu). The mechanism of the migration was implied by incorporation into (4) of the cyclopropyl ring, the opening of which demostrated
[GRAPHICS]A tandem [2 + 2] cycloaddition-Michael reaction using ynolate anions followed by decarboxylation produced polysubstituted five-, six-, and seven-membered cycloalkenes.