Joint preparation of 3-dialkylaminopropionitriles, bis-(2-cyanoethyl) ether and, if desired, ethylene-cyanohydrin

摘要

3-Dialkylaminopropionitriles <IMAGE> I where R1 and R2 are each C1-C4-alkyl which may furthermore be bonded to form a 5-membered or 6-membered ring, bis-(2-cyanoethyl) ether II NC-CH2-CH2-O-CH2-CH2-CN II and, if desired, ethylenecyanohydrin III HO-CH2-CH2-CN III are prepared jointly by a process in which (a) acrylonitrile and water are reacted in the presence of a base at from 60 DEG to 150 DEG C. to give a mixture of acrylonitrile, water and bis-(2-cyanoethyl) ether II, the base being a mineral base, a quaternary nitrogen base or a mixture of these, (b) this mixture is reacted at about 0 DEG -50 DEG C. with a dialkylamine of the general formula IV <IMAGE> IV to give a mixture of water, a dialkylaminopropionitrile I and bis-(2-cyanoethyl) ether II, and this mixture is separated into its components and (c) if desired, the ether II obtained in proces stage (b) or an aqueous solution of this ether and/or the reacted mixtures containing this ether and obtained from process stage (a) or (b) is allowed to react at from 50 DEG to 150 DEG C. with the dialkylamine IV to give a mixture of a 3-dialkylaminopropionitrile I and ethylenecyanohydrin III, and, if desired, the said mixture is separated into its components.