Nitrogen-carbon bonds hydroboration

The reaction of organoboranes with carbon-nitrogen multiple bonds always leads to aminoborane derivatives through a hard-hard interaction. Hydro-boration of nitriles with optically active diisopinocampheylborane (43) constitutes a key step in an asymmetric synthesis of amino acids (44). Carbonyl compounds are deoxygenated via hydroboration of their tosylhydrazones (45). 

With time and without workup, the hydroboration of 125 gave spectral evidence for the formation of intermediates resulting from the migration of the 9-BBN moiety from the R-carbon to a ring nitrogen, with concurrent formation of an exocyclic double bond to an R-carbon of the ring <2002JOC3202>. 

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