The safe handling of borane complexes and alkylboranes (trialkylboranes, dialkylboranes, and trialkylborohydride reagents) and related workup issues are addressed. Oxidation of alkylboranes and quenching of reaction mixtures to safely decompose the reagent or products are discussed. 

Two classes of boron compounds, amine boranes and sodium triacyloxyborohydride are very effective reagents for reductive animations. The mildness of the reduction spares functional groups susceptible to hydrogenation or harsh reduction conditions of other reagents. 

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This amine borane, 5-ethyl-2-methylpyridine borane complex (PEMB) is useful for reductive animations of ketones and aldehydes in methanol or neat. Two of the three hydrides on PEMB are effectively be utilized maximizing the economy of the reagent.  Separation of solid product amine salt can be accomplished via filtration from ionic-liquid substituted pyridine salt.