Hydroxy acids, oligoesters from

Commercially important polyesters, e.g. poly[l-(2-ethylenyl)-2,2,6,6-tetramethyl-4-piperidinylbutane dioate] (146) [190] were synthesized from l-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidines and suitable dicarboxylic acids. Another polymeric HALS was prepared by transesterification of oligoesters of tetramethyl-butane-l,2,3,4-tetracarboxylate with 22,6,6-tetramethyl-4-hydroxypiperidine and 1,10-decanediol [191]. Compound 147 is a similar polyester type HALS. An ester-amide chain is created during esterification of 2-(2,2,6,6-tetramethyl-4-piperidinylamino)ethanol and dimethyl adipate [192]. 

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