Process for the production of the piperidine derivative fexofenadine

摘要

A process for preparing piperidine derivatives of formula (IX), comprising: (a) acylating a compound of formula (21) to produce a mixture of regioisomers of formula (25) (b) recovering from the mixture of regioisomers the compound of formula (VIII), (c) converting the compound of step (b) to the piperidine derivative of formula (IX), with a compound of formula (23), (d) the compound fexofenadine (F) may be produced by further reducing the piperidine derivative of step (c) to provide a piperidine of formula (24), and (e) converting the CO2alkyl moiety of the piperidine derivative of formula 24 to a CO2H moiety to produce fexofenadine (F).