Catecholborane

Chemical Properties

CATECHOLBORANE is clear colorless solution

Uses

Catecholborane is used to prepare B-alkylcatecholboranes. It finds application for the preparation of amides and macrocyclic lactams from carboxylic acids. It is used as a stereoselective reducing agent to convert beta-hydroxy ketones to syn 1,3-diols. Further, it reacts with alkyne through hydroboration to form trans vinyl borane, which is a precursor to Suzuki reaction.

Uses

CATECHOLBORANE is used in the transition metal catalyzed hydroboration of alkenes.1,2,3

reaction suitability

reagent type: reductant

Synthesis

Three types of monohydroboranes, including catecholboranes, were synthesized by high-pressure hydrogen cleavage of B-B bonds of diborates in the presence of non-homogeneous metal catalysts. Among them, palladium catalysts, which can efficiently catalyze the B-B bond cleavage of diborates at ambient temperature and subsequently react with hydrogen to produce catecholboranes, were the most effective catalysts.

Purification Methods

It is a moisture-sensitive flammable liquid which is purified by distillation in a vacuum under a N2 atmosphere and stored under N2 at 0-4o. It liberates H2 when added to H2O or MeOH. A solution in THF, after 25hours at 25o, has residual hydride of 95% (under N2) and 80% (under air) [Brown & Gupta J Am Chem Soc 97 5249 1975].