Stereospecific solid state sodium borohydride reductions of cage diketones

Article abstract of DOI:10.1016/S0040-4020(01)82311-5

Solid state reductions of carbonyl groups in three cage diketones, 1a-1c, have been performed by using sodium borohydride, and the results thereby obtained have been compared with the corresponding reductions performed in ethanol solution. In each case, the solid state reduction proceeds stereospecifically; hydride transfer occurs exclusively at the exo face of the carbonyl group. In contrast, the corresponding homogeneous (solution-phase) reductions display only moderate stereoselectivity.