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Published on: August 16, 2018
Chemoselective Alkylations with N- and C-Metalated Nitriles
Xun Yang1, Dinesh Nath1, Fraser F Fleming1
1Department of Chemistry and Biochemistry, Duquesne University , Pittsburgh, Pennsylvania 15282-1530, United States.
Abstract:
Metalated nitriles exhibit complementary chemoselectivities in electrophilic alkylations. N-Lithiated or C-magnesiated nitriles can be prepared from the same nitrile precursor and selectively reacted with a 1:1 mixture of methyl cyanoformate and benzyl bromide or bifunctional electrophiles through chemoselective attack onto either an alkyl halide or a carbonyl electrophile. A mechanistic explanation for the chemoselectivity preferences is provided that rests on the structural and complexation differences between N- and C-metalated nitriles.
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