Halonium-initiated double oxa-cyclization cascade as a synthetic strategy for halogenated furo[3,2-c]pyran-4-ones.
نویسندگان
چکیده
The reaction of 1-alkenoylcyclopropane carboxylic acids with NBS or NIS was investigated, which provides an efficient route to biologically important 7-halogenated furo[3,2-c]pyran-4-ones in a one-pot transformation. The major pathway for the formation of the O-O heterocycles was proposed as a halo-oxa-cyclization, HBr elimination, cyclopropane ring-opening and recyclization (intramolecular oxa-cyclization), and bromination cascade. The double-oxa-cyclization represents a novel synthetic strategy towards functionalized furo[3,2-c]pyranones.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 11 41 شماره
صفحات -
تاریخ انتشار 2013