Palladium-catalyzed C-alkylations of the highly acidic and enolic triacetic acid lactone. Mechanism and stereochemistry

M Moreno-Manas, J Ribas, A Virgili

Index: Moreno-Manas, Marcial; Ribas, Jordi; Virgili, Albert Journal of Organic Chemistry, 1988 , vol. 53, # 22 p. 5328 - 5335

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Citation Number: 53

Abstract

4-Hydroxy-6-methyl-2-pyrone (triacetic acid lactone)(1) is efficiently alkylated at C-3 with primary and secondary allylic substrates under thermodynamic control by using palladium (0) catalysts. Controlled hydrogenation of the resulting allylated derivatives affords pyrones with saturated chains at C-3. Allylic alkylations occur with retention of configuration at the allylic center, probably through a reversible kinetically favored 0-alkylation.