Rhodium promoted isomerisation of allylic alkoxides: A new method for enolate anion formation
Transition metal mediated isomerisation of allylic alkoxides is presented as a new method for enolate anion generation. The scope and limitations of enolate formation with the catalysts [Rh(dppe)(THF)2]+ClO4- and (Ph3P)3RhCl are explored and the synthetic potential of the methodology demonstrated in the stereoselective formation and reactions of certain ketone and aldehyde enolates.
Gazzard, Lewis J.,Motherwell, William B.,Sandham, David A.
p. 979 - 993
(2007/10/03)
TRAPPING REACTION OF ENOLATES FROM LITHIUM DIMETHYLCUPRATE CONJUGATED ADDITION: IMPORTANCE OF STERIC FACTORS AND, PARTICULARLY, OF β-SUBSTITUTION OF ENONE IN THE C- vs. O-ACYLATION
Conjugated addition of lithium dimethylcuprate to α,β-unsaturated ketones gives intermediate enolates which, treated with acetyl chloride, undergo O- and/or C-acylation depending on the substitution at the enone β-carbon.Results agree with the hypothesis that C-acylation proceeds through an intramolecular metal-assisted mechanism.