Cyclopropanation of styrenes and stilbenes using lithiomethyl trimethylammonium triflate as methylene donor.
نویسندگان
چکیده
Lithiomethyl trimethylammonium triflate, prepared from tetramethylammonium triflate, cyclopropanates several styrenes and stilbenes with electron-donating and selected electron-withdrawing substituents efficiently. Kinetic data support a stepwise nucleophilic addition-ring closure mechanism for this methylenation.
منابع مشابه
A lithiomethyl trimethylammonium reagent as a methylene donor.
Straightforward deprotonation of soluble tetramethylammonium salts with alkyllithium reagents gives lithiomethyl trimethylammonium reagents. Coordination of the Li cation is crucial to the stability of these 'N-C ylides'. These reagents were used to prepare epoxides, aziridines and allylic alcohols.
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ورودعنوان ژورنال:
- Chemical communications
دوره 50 73 شماره
صفحات -
تاریخ انتشار 2014