PROCESS FOR PURIFYING STERICALLY HINDERED 4-AMINO PIPERIDINES

摘要

A process for purifying raw piperidines of formula (I), where R1 to R4 are C 1 to C6 alkyl, R1 and R2 and/or R3 and R4 together are a CH2 chain with 2 to 5 C atoms. Said process is characterized in that in an initial step high-boiling-point substances and possible water are eliminated by distillation from the raw piperidines, in a second step 0.01 to 5 wt %, in relation to the product of the first step, of a reducing agent are add ed and in a third step the piperidines are isolated by distillation.