Regiocontrol in Alkylation of Lithium Dienediolates of Unsaturated Carboxylic Acids
31 December 2001 (online)
Alkylation of dienediolates from unsaturated carboxylic acids with benzylic halides often results in mixtures of regioisomers. However it can be controlled by adequate modification of the reaction conditions. Thus, addition of DMI leads mainly to the α-regioisomer, whereas addition of 12-crown-4 allows to obtain the γ-regioisomer as the major product from the same reactants.
alkyl halides - carboxylic acids - chelates - regioselectivity - solvent effects