Amidophosphine Boranes as Hydroboration Reagents for Nitriles, Alkynes, and Carboxylic Acids.

We report here the hydroboration of nitriles, alkynes, and carboxylic acids using amidophosphine boranes {(BH)(PPh)-NC(CH)}, {(BH)(PPh)N(CH)CH}, and {(BH)(PPh)N-(BH)CHCHN} as reducing agents. These compounds were synthesized to replace more commonly used borane reagents. Solid amidophosphine boranes, which were synthesized with ease, demonstrated excellent reactivity and functional group tolerance toward a wide variety of nitriles, alkynes, and carboxylic acids, affording the corresponding ammonium salts, alkenes, and alcohols in good yield.