3230-76-0Relevant articles and documents
Reduction method for intermediate of vitamin A
-
Paragraph 0015, (2016/12/01)
The invention relates to a reduction method for an intermediate of vitamin A. The method comprises the following steps: (1) preparing a trans-C6 alcohol di-Grignard reagent, and cooling the trans-C6 alcohol di-Grignard reagent to a certain temperature; (2) dissolving C14 aldehyde into toluene or dichloromethane, dropwise adding the solution into the solution obtained in the step (1), and continuing to carry out a reaction for a certain time while carrying out heat preservation after the dropwise adding is completed; (3) hydrolyzing the reaction solution obtained in the step (2) by an acid, so as to obtain a condensate; (4) mixing the condensate obtained in the step (3) with glacial acetic acid, adding zinc powder into the mixture with intense stirring, holding temperature during reaction, continuing to carry out a reaction while carrying out heat preservation, stopping the reaction when the raw material residual is lower than 2%, carrying out washing by water, and recovering a solvent from an organic layer, so as to obtain a reduction product, i.e., crude oil. According to the method, the vitamin A is synthesized by using waste materials, so that the problem that a Lindlar catalyst is prone to poisoned deactivation in a trans condensate is avoided, the cost is reduced greatly, the production process is simplified, the production of trans-C6 alcohol in a production process is avoided, and the environmental protection is facilitated.
