CATALYTIC HYDROGENATION OF ACETYLENIC PHOSPHONIUM SALTS

摘要

Compounds of the formula: I wherein R1 is a 2,6,6-trimethyl-1-cyclohexen-1-yl or 2,3,6-trimethylphenyl group, either of which may be unsubstituted or substituted by a hydroxy group or a protected hydroxy group, R2 is aryl, and X- is an anion are manufactured by hydrogenating a compound of the formula: II wherein R1, R2 and X(-) are as above, in an organic solvent or aqueous-organic solvent in the presence of a nickel-, palladium-, platinum-, cobalt-, rhodium-, iridium-, or ruthenium-containing catalyst. The process is suitable as an intermediate step in carotenoid and retinoid syntheses.