Synthesis of N-styrenyl amidines from α,β-unsaturated nitrones and isocyanates through CO2 elimination and styrenyl migration.

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.

Synthesis of 1,4-enamino ketones by [3,3]-rearrangements of dialkenylhydroxylamines.

The synthesis of 1,4-enamino ketones has been achieved through the [3,3]-rearrangement of dialkenylhydroxylamines generated from the addition of N-alkenylnitrones to electron-deficient allenes. The mild conditions required for this reaction, and the simultaneous installation of a fluorenyl imine N-protecting group as a consequence of the rearrangement, avoid spontaneous cyclization of the 1,4-enamino ketones to form the corresponding pyrroles and allow for the isolation and controlled divergent functionalization of these reactive intermediates. The optimization, scope, and tolerance of the new method are discussed with demonstrations of the utility of the products for the synthesis of pyrroles, 1,4-diones, and furans.

rac-cis-Dicarbonyl-chlorido{1-[2-(diphenyl-phosphanyl-κP)benz-yl]-3-(phenyl-κC(1))imidazol-2-yl-idene-κC(2)}ruthenium(II) dichloro-methane monosolvate.

In the title compound, [Ru(C(28)H(22)N(2)P)Cl(CO)(2)]·CH(2)Cl(2), the Ru(II) atom exhibits a distorted octa-hedral coordination geometry. The N-phenyl group of the ligand has undergone orthometalation; as a result, the tridentate phosphane-functionalized N-heterocyclic carbene ligand is coordinating in a meridional fashion. This complex is of inter-est with respect to transfer hydrogenation catalysis and also provides an example of C-H activation behavior in late transition metal complexes.