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 a...

The Ullmann reaction uses copper metal to convert aryl halides into biaryl compounds. It was first reported in 1901 by Fritz Ullmann and his student Bielecki, and is named after Fritz Ullmann. Although the reaction mechanism is not yet fully understood, two major pathways have been proposed. One is a...

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...

Newman–Kwart Rearrangement (NKR) refers to the thermal rearrangement of O-thiocarbamates to their corresponding S-thiocarbamates under high-temperature conditions. The reaction is named after its discoverers, Melvin Spencer Newman and Harold Kwart. The NKR is an important method for the synthesis of thiophenols and their derivatives. Reagents: Solvent (e.g., DMA, NMP) Reactant:...

The Michaelis–Arbuzov reaction (also known simply as the Arbuzov reaction) refers to the transformation where trivalent phosphite esters react with alkyl halides to produce pentavalent alkyl phosphonates. The reaction was first discovered by August Michaelis in 1898 and later thoroughly investigated by Aleksandr Arbuzov. The Michaelis–Arbuzov reaction is one of...

The Finkelstein Reaction involves the substitution of a halogen atom in an alkyl halide with another halogen atom via an SN2 reaction, using acetone and a metal halide salt. The driving force behind the reaction is the lower solubility of the newly formed metal halide salt in acetone compared to...