The hydroboration of 2- and 3-dibromo and dichioromethylene 5α-androstanes has been shown to afford the 2β-and 3α- and 3β-hydroxymethyl-5α-androstanes respectively; a 3-chloro substituent changed both the regio- and stereochemistry of the hydroboration of a 3,5-diene.
For reviews of directing effects see: ZaidlewiczM. in Comprehensive Organometallic Chemistry Ed., Sir WilkinsonG., StoneF.G.A., and AbelE.W., Pergamon Press, Oxford, 1982, vol. 7, chap. 45.5 p. 229; VaultierM., and CarboniB., Comprehensive Organometallic Chemistry II, Ed. E.W. Abel, F.G.A. Stone, and Sir G. Wilkinson, and A. McKillop, Pergamon Press, Oxford, 1995, vol.7, chap. 5, p. 191.
2.
BrownH.C., and SharpR.L., J. Am. Chem. Soc., 1968, 90, 2915.
3.
PastoD.J., and SnyderR., J. Org. Chem., 1966, 31, 2773.
4.
PastoD.J., and HickmanJ., J. Am. Chem. Soc., 1967, 89, 5608.
5.
Al-FootiK., HansonJ.R., and UyanikC., J. Chem. Res., (S), 1999, 304; (M), 1320.
6.
AppelR., Angew. Chem. (Int.Ed.), 1975, 14, 801.
7.
GuestJ.E., and DjerassiC., J. Am. Chem. Soc., 1964, 86, 5544.
8.
DheghenghiR., and GaudryR., Can. J. Chem., 1962, 40, 818
9.
BoyntonJ.A., HansonJ.R., and LimanM.D., J. Chem. Res., (S), 1998, 376; (M) 1616.
