title: Transition-metal-promoted hydroboration of alkenes: a unique reversal of regioselectivity.
abstract: When hydroboration of 1-octene is carried out in the presence of catalytic amounts of rhodium trichloride followed by the usual oxidation (hydrogen peroxide in aqueous alkali), only minor proportions of 1-octanol (2.4%) are formed accompanied by very significant amounts of 2- (17.4%), 3- (36.9%), and 4-octanol (43.3%). These product compositions are obtained in good overall yield when the borane-THF complex is slowly added to a stirred solution of 1-octene in THF solvent containing the rhodium trichloride. Isomerization of 1-octene to 2-, 3-, and 4-octene in the presence of rhodium trichloride alone is far too slow to account for the foregoing results. The mechanism likely involves multiple and reversible addition/elimination of a Rh-activated B-H species across the double bonds.
authors.affiliation: Department of Chemistry, Rochester Institute of Technology, Rochester, New York 14623, USA. tcmsch@ritvax.isc.rit.edu
authors.forename: Terence C
authors.initials: TC
authors.lastname: Morrill
authors.forename: Christopher A
authors.initials: CA
authors.lastname: D'Souza
authors.forename: Lu
authors.initials: L
authors.lastname: Yang
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Sampognaro