Zhejiang Nhu Company Ltd.

Zhejiang University

Shandong Nhu Pharmaceutical Co., Ltd.

Ming Yu

Haoran Li

Yougui Zhou

Jintao Yuan

Yuhong Zhang

Weikang Shao

Zhirong Chen

Lei Zhao

Yin Zhang

Ming Feng

Fuxiang Deng

Haidong Yu

Yu Ding

Xiandong Zhu

Wenwu Yan

Guangxiong Yu

Wei Xue

Weiwei Su

Sheng Yu

Xingxing Shi

Yu Sheng

The present invention discloses a method for preparing sucralose-6-acetate in a biphasic liquid-liquid system. The method comprises slowly dropwise adding an inert non-polar solvent containing a chlorinating agent to an N,N-dimethyl formamide (DMF) solution of sucrose-6-acetate; then reacting the biphasic liquid-liquid mixture at a certain temperature for 9-20 hours; cooling the system to room temperature after stopping heating, and settling the solution to form layers, an upper layer being an inert non-polar solvent layer, and a lower layer being a DMF solution layer containing the product; hydrolyzing, neutralizing, and filtering the lower layer to obtain a filtrate, and then concentrating the filtrate to obtain a concentrate; dissolving the concentrate in water, and obtaining the product by extraction using ethyl acetate and crystallization, the inert non-polar solvent being an alkane solvent containing 8-18 carbon atoms that is not mutually soluble with DMF. The method has a high product yield, and can significantly reduce the decomposition of DMF, thereby reducing costs.

Method for preparing sucralose-6-acetate in biphasic liquid-liquid system

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 &#x3b1;, &#x3b2;-unsaturated aldehydes or &#x3b1;, &#x3b2;-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.

Method for preparing optically active carbonyl compound

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.

Metal complex catalyst, preparation method thereof, and use thereof in preparing D,L-menthol

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Shaoxing, China

Ming Yu