Piperidine → 3-[4-(2,2,3,3-Tetrafluoropropoxy)phenyl]prop-2-enenitrile

Participants

Reaction Steps

A mixture of 500 g of 4-(2,2,3,3-tetrafluoropropoxy)benzaldehyde, 183 g of cyanoacetic acid, 250 ml of pyridine and 250 ml of piperidine are heated with stirring and allowed to react for 1 hour at 110° C. A further 36.6 g of cyanoacetic acid are then added and the mixture is allowed to react for a further 30 minutes at 110° C. The reaction mixture is cooled, distilled under reduced pressure and 433.1 g of 4-(2,2,3,3-tetrafluoropropoxy)cinnamonitrile are obtained (yield: 78%; purity 95%) in the form of a mixture of isomers which contains cis-4-(2,2,3,3-tetrafluoropropoxy)cinnamonitrile and trans-4-(2,2,3,3-tetrafluoropropoxy)cinnamonitrile in a molar ratio cis:trans of approximately 1.35 to 1.8:1 (corresponding to a weight ratio of about (58 to 64):(42 to 36)) and in addition up to about 3% by weight of piperidine and 2% by weight of unidentified impurities and resins.

Provenance & Evidence