Method for preparing 2,2-dimethyl-3-hydroxy propanal

Abstract

The invention provides a method for preparing 2,2-dimethyl-e-hydroxy propanal. The method is characterized by comprising the following step of: catalyzing a condensation reaction between isobutylaldehyde and formaldehyde by taking a compound having a structure shown in the specifications as a catalyst to obtain 2,2-dimethyl-e-hydroxy propanal, wherein n is equal to 2-11, m is equal to 2-6, and R is H or alky of C1-C8. In the preparation method, the consumption of the catalyst is small, and the catalyst is easy to recycle. Moreover, the reaction condition is mild, and the post treatment is simple. The transformation rate of the isobutyl aldehyde is over 99 percent, and the selectivity of hydroxyl pivalaldehyde is over 98 percent.

Description

technical field The invention belongs to the field of preparation of chemical intermediates, in particular to the preparation of 2,2-dimethyl-3-hydroxypropanal. Background technique 2,2-Dimethyl-3-hydroxypropanal (commonly known as hydroxypivalaldehyde, 2,2-dimethyl-3-hydroxypropanal, referred to as HPA,) is a synthetic 2,2-dimethyl-1,3-propanediol (commonly known as neopentyl glycol, Neopentyl glycol, referred to as the intermediate product of NPG). As an important fine chemical product and raw material, NPG is widely used in the production of various resins, plasticizers, synthetic lubricants and surfactants. Formaldehyde solution and isobutyraldehyde (IBD) are usually used in industry at present, and triethylamine (triethlamine, referred to as TEM) is used as a catalyst to generate aldol condensation reaction to synthesize 2,2-dimethyl-3-hydroxypropionaldehyde, and hydrogenation Or disproportionation reaction to generate neopentyl glycol. This method often has the dis...

AI Technical Summary

Problems solved by technology

This method has the disadvantages of high unit consumption of formaldehyde, difficult recovery of catalysts using inorganic bases, easy corrosion of equipment, neutralization and separation of the generated liquid, complex reaction process, long production cycle, and the by-product sodium formate affects product quality and other shortcomings.

The condensation reaction in CN1286673A uses anion exchange resin, and the conversion rate of HPA is between 91-93%, while the anion exchange resin often has the disadvantages of short active cycle, low raw material conversion rate and product selectivity