Addition compounds of alkali metal hydrides—XIX : Rapid reaction of trialkylboranes with lithium aluminum hydride in the presence of triethylene-diamine. A facile and quantitative synthesis of lithium trialkylborohydrides, including derivatives with exceptionally large steric requirements

Abstract

Trialkylboranes react rapidly with lithium alumimum hydride (LAH) in diethyl ether in the presence of triethylenediamine (TED) at 0° to form the corresponding lithium triakylborohydrides and aluminum hydride. The aluminum hydride precipitates out of solution as its triethylenediamine adduct. The reaction is applied to a wide variety of triakylboranes. Consequently, the present reaction provides a general, convenient synthesis of lithium trialkylborohydrides including those with exceptionally large steric requirements.