Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
J Am Chem Soc. 2012 Feb 15;134(6):2966-9. doi: 10.1021/ja300031w. Epub 2012 Feb 1.
To date, effective nickel-catalyzed enantioselective cross-couplings of alkyl electrophiles that bear oxygen leaving groups have been limited to reactions of allylic alcohol derivatives with Grignard reagents. In this Communication, we establish that, in the presence of a nickel/pybox catalyst, a variety of racemic propargylic carbonates are suitable partners for asymmetric couplings with organozinc reagents. The method is compatible with an array of functional groups and utilizes commercially available catalyst components. The development of a versatile nickel-catalyzed enantioselective cross-coupling process for electrophiles that bear a leaving group other than a halide adds a significant new dimension to the scope of these reactions.
迄今为止，有效实现含离去基团的烷基亲电试剂的镍催化对映选择性交叉偶联反应仅限于烯丙醇衍生物与格氏试剂的反应。在本通讯中，我们证明，在镍/吡咯烷酮催化剂的存在下，各种外消旋丙炔碳酸酯是与有机锌试剂进行不对称偶联的合适伙伴。该方法与一系列官能团兼容，并使用市售的催化剂组分。发展一种用于除卤化物以外的离去基团的亲电试剂的多功能镍催化对映选择性交叉偶联过程，为这些反应的范围增添了一个显著的新维度。
