The syntheses of a series of oxygenated cyclohexene ring A synthohs 20, 22-27, 34, 36, and 37 that possess suitable functionality for further elaboration for taxoid synthesis are described. These compounds have been prepared from β-ionone by a series of oxidative and addition reactions or alternatively by Lewis acid catalyzed Diels-Alder cycloadditions with the oxygen-containing trimethyl substituted dienes 31 and 33. Key words: taxoid, ...
