Department of Chemistry, Life Science and Engineering Building, Boston University, 24 Cummington Street, Boston, Massachusetts 02215, USA.
Org Lett. 2011 Aug 5;13(15):4020-3. doi: 10.1021/ol201535b. Epub 2011 Jul 6.
Chiral biphenols catalyze the enantioselective asymmetric propargylation of ketones using allenylboronates. The reaction uses 10 mol % of 3,3'-Br(2)-BINOL as the catalyst and allenyldioxoborolane as the nucleophile, in the absence of solvent, and under microwave irradiation to afford the homopropargylic alcohol. The reaction products are obtained in good yields (60-98%) and high enantiomeric ratios (3:1-99:1). Diastereoselective propargylations using chiral racemic allenylboronates result in good diastereoselectivities (dr >86:14) and enantioselectivities (er >92:8) under the catalytic conditions.
手性联苯酚催化酮的对映选择性不对称炔丙基化反应，使用烯丙基硼酸酯作为亲核试剂。该反应在无溶剂、微波辐射条件下，以 10 mol%的 3,3'-Br(2)-BINOL 为催化剂，以烯丙基二氧硼烷作为亲核试剂，得到高收率（60-98%）和高对映选择性（3:1-99:1）的同型炔丙醇。在催化条件下，手性外消旋烯丙基硼酸酯的对映选择性炔丙基化反应可以获得良好的非对映选择性（dr>86:14）和对映选择性（er>92:8）。
