Alkadienyl-cyclohexenone derivative production, for use as carotenoid intermediate, by catalytic hydrogenation of alkenynyl-cyclohexenone derivative over catalyst containing iron

摘要

Production of 5-hydroxy-3-methyl-penta-1E,3E-dienyl- or 3-hydroxy-3-methyl-penta-1E,4-dienyl-cyclohexenone derivatives (I) or (II) by catalytic hydrogenation of 5-hydroxy-3-methyl-pent-3E-en-1-ynyl- or 3-hydroxy-3-methyl-pent-4-en-1-ynyl-cyclohexenone derivatives (III) or (IV) is carried out in presence of a catalyst containing iron. Production of alkadienyl-cyclohexenone derivatives of formula (I) or (II) by catalytic hydrogenation of alkenynyl-cyclohexenone derivatives of formula (III) or (IV) is carried out in presence of a catalyst containing iron. [Image] R1>4-(hydroxy or 1-4C acyloxy)-3-oxo-2,6,6-trimethyl-cyclohex-1-enyl, 1-hydroxy-4-oxo-2,6,6-trimethyl-cyclohex-2-en-1-yl, 3-oxo-2,6,6-trimethyl-cyclohex-1-enyl or a bicyclic group of formula (a); R2>OH or protecting group converted into OH by hydrolysis; R3>, R4>H or 1-4C alkyl. [Image].