Hydroboration Hydroboration Definition: Hydroboration is the treatment of alkynes with BH3, followed by H2O2 in which aldehydes and ketones are obtained. Hydroboration Explained: Hydroboration is a two-step reaction sequence which proceeds via an anti-Markovnikov addition where installing a hydroxyl group at…
Hydrate formation [H2O] Hydrate formation [H2O] Definition: Treatment of a carbonyl compound with H2O in the presence of acid or base catalyst adds the elements of H and OH across the carbonyl bond, forming a gem-diol or hydrate. Hydrate formation [H2O] Explained: The…
Hofmann rearrangement Hofmann Rearrangement Definition: When amides are treated with halide and base, a rearrangement occurs, resulting in the loss of carbon dioxide and the formation of an amine. Hofmann rearrangement Explained: The Hofmann rearrangement is a special halogenation reaction…
Hofmann Elimination Hofmann Elimination Definition: Tetra-alkyl ammonium salts undergo elimination to form the least substituted alkene. This is called the Hofmann elimination. Hofmann Elimination Explained: Amines, like alcohols, contain a poor leaving group which must be converted…
Hell-Vollhard-Zolinsky Reaction Hell-Volhardt-Zelinsky Reaction Definition: The Hell-Volhardt-Zelinsky [HVZ] reaction is a means of converting a carboxylic acid to a brominated carboxylic acid (the bromine ends up on the α carbon…
Heck Reaction Heck Reaction Definition: The Heck reaction is a coupling reaction of a vinyl or aryl halide with an alkene in the presence of a palladium catalyst which forms a more highly substituted alkene with a new carbon-carbon bond. Heck reaction Explained: The Heck reaction is the…
Halogenation [Cl2, Br2, I2] Halogenation Definition: In the same way as alkenes, alkynes are also observed to undergo halogenation. The one major difference is that alkynes have two π bonds…
Haloform reaction Haloform reaction Definition: Addition of a dihalogen (such as iodine, bromine, or chlorine) to a methyl ketone in the presence of base results in a carboxylic acid and a haloform (iodoform, bromoform, or chloroform). Haloform reaction Explained: Haloform reaction is…
Grignard formation [alkyl halides] Grignard formation [alkyl halides] Definition: Treatment of alkyl halides with magnesium metal leads to the formation of Grignard reagent. Grignard formation [alkyl halides] Explained: A Grignard reagent has a formula RMgX where X is a…
Grignard formation [alkenyl halides] Grignard formation [alkenyl halides] Definition: Treatment of an alkenyl halide with magnesium metal leads to the formation of the Grignard reagent. Grignard formation [alkenyl halides] Explained: A Grignard reagent has a formula RMgX where X…