Abstract: The present invention discloses a method for preparing optically active carbonyl compound, comprising the following steps: under the catalysis of chiral amine salt and transition metal catalysts, with hydrogen and catalytic amount of dihydropyridine compound as hydrogen source, use ?, ?-unsaturated aldehydes or ?, ?-unsaturated troponoid compounds to conduct asymmetric catalytic reaction to obtain the optically active carbonyl compound. This method comes in moderate reaction condition, simple operation, and catalytic amount of dihydropyridine compounds usage, the target product is easy to be separated and purified from the reaction system, and the metal catalyst can be recycled, it is economical.

Abstract: The present invention discloses a metal complex catalyst, its preparing method and its application in preparing D,L-menthol, the metal complex catalyst includes weight percent elements as follows: 70-85% of Ni, 8-10% of Al, 5-10% of V, and 2-10% of Co. When this metal complex catalyst is applied in preparing D,L-menthol through thymol hydrogenation, it has the characteristics of high reaction activity and quick racemization of chiral compound. Meanwhile, a certain kind of alkali added in isomerization is the key to reducing light constituent byproduct. The whole process comes in good reaction selectivity, simple preparing technology, low production cost, and environment-friendly synthetic route.

Abstract: The present invention discloses a metal complex catalyst, its preparing method and its application in preparing D,L-menthol, the metal complex catalyst includes weight percent elements as follows: 70-85% of Ni, 8-10% of Al, 5-10% of V, and 2-10% of Co. When this metal complex catalyst is applied in preparing D,L-menthol through thymol hydrogenation, it has the characteristics of high reaction activity and quick racemization of chiral compound. Meanwhile, a certain kind of alkali added in isomerization is the key to reducing light constituent byproduct. The whole process comes in good reaction selectivity, simple preparing technology, low production cost, and environment-friendly synthetic route.

Abstract: The present invention discloses a method for preparing optically active carbonyl compound, comprising the following steps: under the catalysis of chiral amine salt and transition metal catalysts, with hydrogen and catalytic amount of dihydropyridine compound as hydrogen source, use ?, ?-unsaturated aldehydes or ?, ?-unsaturated troponoid compounds to conduct asymmetric catalytic reaction to obtain the optically active carbonyl compound. This method comes in moderate reaction condition, simple operation, and catalytic amount of dihydropyridine compounds usage, the target product is easy to be separated and purified from the reaction system, and the metal catalyst can be recycled, it is economical.