Synthesis of N-styrenyl amidines from α,β-unsaturated nitrones and isocyanates through CO2 elimination and styrenyl
Dong-Liang Mo1, Wiktoria H Pecak, Meng Zhao
1Department of Chemistry, University of Illinois at Chicago , Chicago, Illinois 60607, United States.
Abstract:
A mild, metal-free, and modular route for the preparation of N-styrenyl amidines from N-aryl-α,β-unsaturated nitrones and isocyanates has been developed that accesses an initial oxadiazolidinone intermediate that can undergo CO(2) elimination and styrenyl migration. The use of a migration event to install N-styrenyl amidine substituents circumvents a limitation of traditional Pinner-type methods for amidine synthesis that require the use of amine nucleophiles. The modularity of the nitrone and isocyanate reagents provides access to a variety of differentially substituted N-styrenyl amidines. The scope and tolerance of the method are presented, and preliminary mechanistic data for the transformation are discussed.
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