DiphepanolDiphepanol is a cough suppressant.SynthesisEx 1: The α-keto bromination of propiophenone gives 2-bromopropiophenone . Displacement of the halogen and hence amination with piperidine gave alpha-Piperidinopropiophenone, . and addition of phenyl Grignard reagent to give the benzhydrol product, and hence Dihepanol.