PRODUCTION OF DIMETHYLOLALKANOIC ACID

摘要

PROBLEM TO BE SOLVED: To make readily crystallizable demethylolalkanoic acid, by bringing a reaction solution containing a trialkylamine catalyst into contact with a nonpolar organic solvent to efficiently separate the catalyst. SOLUTION: (B) A nonpolar organic solvent is brought into contact with (A) a solution of a reaction product containing a dimethylolalkanal of the formula (R is a 1-7C alkyl) obtained by condensing (i) a 3-9C aliphatic aldehyde containing two hydrogen atoms on an α-carbon atom or an α-alkylacrolein with (ii) formaldehyde in the presence of (iii) a trialkylamine catalyst (preferably, triethylamine or tripropylamine catalyst) and water. The component iii is selectively extracted in the component B from the reaction product solution. The component B layer is separated form the reaction product solution layer by phase separation and the reaction product solution layer is oxidized with (C) hydrogen peroxide to give an oxidation reaction solution containing a dimethylol alkanoic acid, which is crystallized with an organic solvent.