PROCESS FOR THE PREPARATION OF ESTERS OF MERCAPTOALCANOLS WITH HYDROXYPHENYLCARBOXYLIC ACIDS

摘要

Compounds of formula I (I) where R1 and R2 independently are alpha-branched alkyl of 3 to 8 carbon atoms, R3 is hydrogen, R4 is ethylene, 1,3-propylene or 1,4-butylene, and n is 2 or 4 are effective stabilizers for protecting elastomeric or acrylonitrile copolymer compositions or lubricating oil compositions against thermal oxidation and discoloration. 2-Mercaptoethyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate is particularly useful.