Carboxylic acids can be protected by conversion to a methyl ester using diazomethane. The diazomethane abstracts a proton to make a carboxylate, which undergoes an SN2 reaction with the methyldiazonium ion, releasing nitrogen gas to form the ester. The carboxylic acid is regenerated when hydroxide attacks the carbonyl to release...

The Grubbs reaction is a method for achieving olefin metathesis using ruthenium (Ru) carbene catalysts (the Grubbs catalyst series), developed by Professor Robert H. Grubbs. Olefin metathesis was first discovered by accident in the 1950s. It refers to the process in which olefins, in the presence of metal carbene catalysts,...

The Hofmann rearrangement converts an amide into a primary amine with the loss of one carbon atom. First, a base deprotonates the amide. The deprotonated amide then attacks a halogen, forming an N‑haloamide. Subsequently, the N‑haloamide is deprotonated by base to give an N‑haloamide anion salt. This salt rapidly undergoes...

Hoffmann Elimination is a reaction in which an amine containing β-hydrogens is converted into an alkene under heating conditions, using iodomethane, water, and silver oxide. It is named after the German chemist August Wilhelm von Hofmann.The Hofmann elimination offers an efficient method for synthesizing alkenes from amines, especially when conventional...

284963 The Pechmann condensation is a reaction in which phenols and β-keto esters react under acid catalysis to synthesize coumarin derivatives. It was first discovered by German chemist Hans Freiherr von Pechmann and is named after him. Coumarins are important intermediates in pharmaceuticals, agrochemicals, and functional materials. This reaction offers...

The Pinner Reaction refers to the acid-catalyzed reaction of nitriles with alcohols to form imidate salts (alkyl imidate hydrochlorides), known as Pinner salts, which can further react with water or ammonia to yield esters or amidines. This reaction was first discovered in 1877 by Adolf Pinner and is named after...