Carboxypeptidase A catalyzed .alpha.,.beta.-elimination reactions: rapid catalysis of .alpha.,.beta.-elimination of hydrogen chloride from .beta.-chloro ketone substrates
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
The in situ oxidation–Wittig reaction of α-hydroxyketones
作者:Karen A. Runcie、Richard J. K. Taylor
DOI:10.1039/b201513g
日期:2002.4.19
In situ oxidationâWittig methodology has been applied to α-hydroxyketones avoiding the problems normally associated with α-ketoaldehydes; the procedure is practically simple, and in many cases gives high yields of the product γ-ketocrotonates; the procedure has also been successfully utilised with ethyl glycolate and glycolaldehyde dimer.
A TMG catalyzed, practical and efficient hydrophosphorylation of 4-oxo-enoates by diethyl or diphenyl phosphite has been described. This protocol allows a convenient access to a variety of enol phosphates under mild conditions in good yield with excellent stereoselectivity.