Production of Quinolyl and Pyridyl Anions during Decarboxylation

Abstract

IT has been shown1,2that when picolinic and quinaldinic acids are decarboxylated in the presence of aldehydes and ketones, α-pyridyl and α-quinolyl carbinols of the type Py(Qy).CH(OH).R are produced in good yields (40–80 per cent). The course of this reaction has been formulated in terms of the intermediate formation of α-pyridyl and α-quinolyl anions, which are formally of cyanide ion type1,2. The possibility that the cyanide function might by conjugation be extended to the γ-position has been confirmed recently by Mislow3, who has obtained γ-pyridyl diphenylcarbinol by the decarboxylation of isonicotinic acid in benzophenone. We now report that we have prepared γ-quinolyl diphenylcarbinol, m.p. 247°, from cinchoninic acid and benzophenone in yields of 7–10 per cent; we are developing the reaction as a possible route to quinine analogues.