Stereocontrol in <i>N</i>-Directed Hydroboration: Synthesis of Amino Alcohols Related to the Piperidine Alkaloids
作者:Guoqiang Wang、Edwin Vedejs
DOI:10.1021/ol802781c
日期:2009.3.5
acid induces internal hydroboration with high regiocontrol, even with a terminal alkene (R = H). Good stereocontrol is possible for the N-benzyl substrates. Comparisons with acyclic model structures show that the source of regiocontrol with the terminal alkene is due to a steric effect of the axial piperidine C(3,5) hydrogens that destabilize the competing bridged bicyclic transition state.