Lewis acid-base 1,2-addition reactions: synthesis of pyrylium borates from en-ynoate precursors.
نویسندگان
چکیده
Treatment of methyl (Z)-2-alken-4-ynoates with the strong Lewis acid tris(pentafluorophenyl) borane, B(C6F5)3, yield substituted zwitterionic pyrylium borate species via an intramolecular 6-endo-dig cyclisation reaction.
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عنوان ژورنال:
- Dalton transactions
دوره 45 14 شماره
صفحات -
تاریخ انتشار 2016