A study of [formula omitted] catalysed Wacker reaction for the deprotection of prop-2-enyl and prop-1-enyl ethers

Abstract

Pd(II)Cl 2 (1 mole equivalent)/CuCl/DMF-H 2O/O 2/2h catalysed oxidation of various prop-2-enyl ethers 1a–12a is reported to result in the formation of Wacker ketones 1b,3b,5b,6b,9b,11b,12b (12–51%), hydrolysis products 2c,4c–7c,9c–12c (12–43%) and η 2-vinyl complexes of palladium chloride 2d,4d,7d,8d (52–94%) respectively. The corresponding prop-1-enyl ethers 2e,4e–12e under similar conditions react with a catalytic amount of Pd(II)Cl 2 (0.2 mole equivalent) rapidly (15–20 min.) to give exclusively hydroxy compounds 2c,4c–12c respectively in good yields (75–97%).