Relay catalysis: combined metal catalyzed oxidation and asymmetric iminium catalysis for the synthesis of bi- and tricyclic chromenes.
نویسندگان
چکیده
A catalytic asymmetric oxidative iminium-allenamine cascade allows the use of propargyl alcohols as stable substrates and yields valuable chiral bicyclic 4H-chromenes. A subsequent Michael addition-condensation domino reaction provides complex tricyclic 4H-chromenes in a highly enantioselective fashion.
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ورودعنوان ژورنال:
- Chemical communications
دوره 48 28 شماره
صفحات -
تاریخ انتشار 2012