Phosphine-boronates: efficient bifunctional organocatalysts for Michael addition.
نویسندگان
چکیده
Phosphine-boronates R(2)P(o-C(6)H(4))B(OR')(2) have been evaluated as bifunctional organocatalysts for the Michael addition of malonate pronucleophiles to methylvinylketone. The presence of the Lewis acidic boron center adjacent to phosphorus significantly improves catalytic performance. Isolation and complete characterization of a key intermediate, namely a β-phosphonium enolate, substantiate the role of the Lewis acidic moiety in the catalytic process.
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ورودعنوان ژورنال:
- Chemical communications
دوره 48 37 شماره
صفحات -
تاریخ انتشار 2012