Rosenmund Reaction :
Acylchlorides when hydrogenated over catalyst, palladium on barium Sulphate yield aldehydes. Sulphur and Quinolene can be used as poison.
Ex :
Stephen Reaction :
Nitriles are reduced to corresponding imines with stannous chloride in the presence of Hydrochloric acid, which on hydrolysis give corresponding aldehyde.
