TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The first temperature is greater than or equal to -20 (preferably -10, especially 0, particularly +10) degrees C. The method further involves: c) removing residual anhydrous liquid ammonia from the reaction mixture and, d) removing the organic solvent from the reaction mixture. The first temperature of the reaction mixture is increased to the second temperature via an exothermic reaction of the anhydrous liquid ammonia and the boron containing compound, via an external addition of heat energy or via their combination. The anhydrous liquid ammonia, the boron containing compound or the anhydrous liquid ammonia and the boron containing compound are combined with an organic solvent prior to the step of incorporating the reaction mixture. The ammonium borohydride is formed in situ or ex situ from a metal borohydride salt and an ammonium salt. The ammonium borohydride is formed from a metal borohydride salt and an ammonium salt. Preferred Components: The metal borohydride salt comprises an alkali metal. The alkali metal is selected from: lithium, sodium and potassium (preferably sodium). The ammonium salt is an ammonium halide salt (preferably ammonium chloride, ammonium bromide and/or ammonium iodide, especially ammonium chloride).    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The organic solvent is ether selected from: tetrahydrofuran, glyme, diglyme, triglyme, diethyl ether, dibutyl ether, methyl ethyl ether and/or diethoxyethane. The boron containing compound is selected from: a borane species and/or ammonium borohydride. The borane species is selected from: diborane, Lewis base adduct of diborane, alkyl borane, Lewis Base adduct of an alkyl borane, aryl borane, Lewis base adduct of an aryl borane, ether adduct of borane, ether adduct of alkyl borane, ether adduct of aryl borane, sulfide adduct of borane, sulfide adduct of alkyl borane, sulfide adduct of aryl borane, amine adduct of borane, amine adduct of alkyl borane and/or amine adduct of aryl borane. The borane species is a diborane, a borane tetrahydrofuran complex, dimethylsulfide borane, diethylaniline borane, 2-picoline borane, pyridine borane, tert-butylamine borane, and/or triethylamine borane. EXAMPLE - A pressure reactor was initially charged with sodium borohydrate (NaBH4) powder (38 g) and ammonium chloride (NH4Cl) powder (53 g). The reactor was then further charged with commercial grade anhydrous liquid ammonia (3.5 l) at 5 degrees C. The ammonia was transferred directly from the cylinder without additional purification. The reactor was further charged with tetrahydrofuran (1 l). Once charged with the reactants and ammonia/tetrahydrofuran solvent mixture, the pressure reactor was then sealed and the reaction mixture was stirred for an additional 1 hour, at which time the pressure in the reactor was increased from 58 psig due to the evolution of hydrogen by-product. The reactor was allowed to equilibrate for 30 minutes, at which time the reactor was vented of hydrogen gas by-product to restore the vessel to atmospheric pressure. The reaction mixture was collected and the ammonia was removed which resulted in high yield of ammonia borane. Removal of the tetrahydrofuran (THF) from the filtrate also provided a high yield of ammonia borane as a white solid. The evaporated ammonia was condensed for reuse.