Aminoborohydrides. 9. Selective reductions of aldehydes, ketones, esters, and epoxides in the presence of a nitrile ising lithium N,N-dialkylaminoborohydrides

Article abstract of DOI:10.1016/S0040-4039(96)02410-0

A series of competitive reductions of several functional groups was carried out in the presence of aromatic and aliphatic nitriles using Lithium N,N-dimethylaminoborohydride (LiMe₂NBH₃) or Lithium Pyrrolidinoborohydride (LiPyrrBH₃) as the reducing agents. Both LiMe₂NBH₃ and LiPyrrBH₃ cleanly and quantitatively reduced aldehydes, ketones, esters, and epoxides in the presence of the nitriles to give the corresponding reduction products in yields ranging from 85 to 98%. In no case was the nitrile reduced: no products arising from the reduction of nitriles were detected by GC analysis. Two difunctional nitriles were also reduced to give complete reduction of the more active functional group with no reduction of the nitrile.