The dimethoxyketone 3, synthesized selectively and in high yield from methyl deoxycholate (1), served as a common precursor to three novel steroidal boranes (5, 7, and 10). The complexation behavior of these boranes was probed both by NMR studies and by using them as Diels-Alder catalysts. In the latter case, modest enantiomeric excesses were obtained.