Cannizzaro ReactionMechanism of Cannizzaro ReactionThe reaction begins with a hydroxide attack on the carbonylcarbonfollowedby deprotonation to give a dianion. The unstable dianion releases a hydrideanion, which attacks another molecule of aldehyde. In this process, thedianion converts to a carboxylate anion and the aldehyde to an alkoxide. Thealkoxide then picks up a proton from water to provide the final alcoholproduct. At the same time, the carboxylate is converted to the carboxylic acidproduct after acid workupCannizzaro Reaction Mechanism
Crossed Cannizzaro ReactionIf an aldehyde without any α-hydrogen is made to react with formaldehyde in the presence of a base togive formic acid and an alcohol, it is called crossed Cannizzaro reaction. This reaction is quite useful forsynthesizing a high yield of alcohol.
Reimer Tiemann ReactionWhat is Reimer Tiemann Reaction?Reimer Tiemann reaction is a type of substitution reaction, named after chemists KarlReimer and Ferdinand Tiemann. The reaction is used for the ortho-formylation ofC6H5OH (phenols).