Reaction of trialkylboranes with sodium diethyldihydroaluminate in the presence of 1,4-diazabicyclo[2.2.2]octane. a convenient, general method for preparation of sodium trialkylborohydrides

Abstract

Trialkylboranes in tetrahydrofuran (THF) or diethyl ether (EE) solutions, including those with exceptionally large steric requirements, react readily with toluene solutions of sodium diethyldihydroaluminate in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) to yield the corresponding sodium trialkylborohydrides and diethylaluminum hydride. The diethylaluminum hydride precipitates from solution as its DABCO adduct, with the use of EE as solvent facilitating the separation. This reaction constitutes a convenient, general method for preparing sodium trialkylborohydrides.