Dual catalysis in enantioselective oxidopyrylium-based [5 + 2] cycloadditions.
نویسندگان
چکیده
A new method for effecting catalytic enantioselective intramolecular [5 + 2] cycloadditions based on oxidopyrylium intermediates is reported. The dual catalyst system consists of a chiral primary aminothiourea and a second achiral thiourea. Experimental evidence points to a new type of cooperative catalysis with each species being necessary to generate a reactive pyrylium ion pair that undergoes subsequent cycloaddition with high enantioselectivity.
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 133 37 شماره
صفحات -
تاریخ انتشار 2011