1334218-75-5

Upstream product

• 16533-71-4 3,5-dinitro-p-toluic acid 
• 108157-52-4 (S)-1-(2-piperidino-phenyl)-3-methyl-1-butylamine 
• 219921-93-4 (R)-3-methyl-1-(2-(1-pieridinyl)phenyl)-butylamine 

Downstream Products

• 1334218-78-8 S-PPA*3,5-DNTA 
• 1334218-77-7 R-PPA*3,5-DNTA 

Relevant academic research and scientific papers

Process for the enantiomeric enrichment of 3-methyl-1-(2-piperidinophenyl)-1-butylamine

The present invention relates to a process for the enantiomeric enrichment of 3-methyl-1-(2-piperidinophenyl)-1-butylamine (hereinafter PPA), the process comprising the fractional crystallization of PPA in the form of its acid-addition salt with an achiral carboxylic acid of the formula A, in particular a carboxylic acid of the formula A' as described herein from a solution or emulsion containing a mixture of the enantiomers of PPA and the achiral carboxylic acid of the formula A, preferably in the presence of seed crystals of the acid addition salt of the desired enantiomer of PPA with the achiral carboxylic acid of the formula A, whereby the acid-addition salt of PPA with the achiral carboxylic acid of the formula A is obtained, which is enantiomerically enriched with regard to the desired enantiomer of PPA. wherein n is 0 or 1, k is 0 or 1 and wherein R is C1-C4-alkyl, C1-C4-alkoxy and halogen, in particular methyl, methoxy or chlorine.