The rhodium carbene route to oxazoles: a remarkable catalyst effect.
نویسندگان
چکیده
Dirhodium tetraacetate catalysed reaction of alpha-diazo-beta-keto-carboxylates and -phosphonates with arenecarboxamides gives 2-aryloxazole-4-carboxylates and 4-phosphonates by carbene N-H insertion and cyclodehydration; in stark contrast, dirhodium tetrakis(heptafluorobutyramide) catalysis results in a dramatic change of regioselectivity to give oxazole-5-carboxylates and 5-phosphonates.
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ورودعنوان ژورنال:
- Chemical communications
دوره 22 شماره
صفحات -
تاریخ انتشار 2009