Patent · US Expired

Process for preparing malonic acid and alkylmalonic acids

US5886219A · kind A · utility

51Cited by
3References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 6, 1998
Grant dateMar 23, 1999
Priority date
Expiry dateFeb 6, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C51/09
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Malonic acid and alkylmalonic acids are prepared by a process of acid-catalyzed saponification of malonic acid esters, which comprises: PA1 contacting an aqueous mixture of the ester II with an acid ion exchanger containing sulfonic acid groups at from 30.degree.-100.degree. C. and from 40-1000 mbar according to the following scheme: ##STR1## where R.sup.1 =H, CH.sub.3, PA1 R.sup.2 =H, CH.sub.3 or PA1 R.sup.1 +R.sup.2 =--CH.sub.2 --CH.sub.2 --and PA1 R.sup.3 =CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.7, C(CH.sub.3).sub.3 ; distilling off the alcohol R.sup.3 OH which is formed; PA1 separating the water, with the aid of organic solvents, from the malonic acid or alkylmalonic acid product; and then PA1 isolating the product by crystallization.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.