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A novel metal-free oxidative 1,2-alkylarylation of unactivated alkenes with the α-C(sp³)-H bonds of acetonitriles for the synthesis of 5-oxopentanenitriles is presented. In the presence of TBPB (tert-butyl peroxybenzoate), a variety of α-aryl allylic alcohols underwent the 1,2-alkylarylation reaction with acetonitriles, giving 5-oxopentanenitriles in good to excellent yields. This method proceeds via the C(sp³)-H oxidative coupling with the C-C double bond and 1,2-aryl-migration, and represents a new access to acyclic molecules through metal-free oxidative alkene 1,2-alkylarylation. [ABSTRACT FROM AUTHOR]

A new oxidative coupling of unactivated terminal alkenes with amides using peroxides is described, in which mono- and difunc-tionalization of alkenes are selectively achieved. In this reaction with amides, the chemoselectivity toward the functionalization of the C(sp³)-H bonds adjacent to the nitrogen atom or the functionalization of the carbonyl C(sp²)-H bonds across alkenes relies on the reaction conditions. [ABSTRACT FROM AUTHOR]

Since carbon-based structures of various dimensions, including one-dimensional (1D) carbon nanotubes, two-dimensional (2D) graphene and three-dimensional (3D) carbon foams, have attracted significant attention as microwave absorption fillers, we present an exceptional hetero-junction filler with a 1D–2D–1D feature, achieved by manipulating 2D graphene into 1D carbon fibers in the fiber-extruding process under the electric field. The as-fabricated 1D–2D–1D structural fillers exhibited much-improved dielectric properties and promoted microwave absorption performance in their composites, which is linked to the establishment of enhanced polarization capability, the generation of increased electric loss pathway and the creation of more favorable electromagnetic energy consumption conditions. The results suggest that employing 2D graphene in the 1D–2D–1D nanostructures played the critical role in tuning the electromagnetic response ability, because of its intrinsic electric advantages and dimensional features. To broaden the effective absorption bandwidth, periodic pattern-absorbing structures were designed, which showed combined absorption advantages for various thicknesses. Our strategy for fabricating 1D–2D–1D structural fillers illuminates a universal approach for manipulating dimensions and structures in the nanotechnology. [ABSTRACT FROM AUTHOR]

Since manipulating electromagnetic waves with electromagnetic active materials for environmental and electric engineering is a significant task, here a novel prototype is reported by introducing reduced graphene oxide (RGO) interfaces in carbon fiber (CF) networks for a hierarchical carbon fiber/reduced graphene oxide/nickel (CF-RGO-Ni) composite textile. Upon charaterizations of the microscopic morphologies, electrical and magnetic properties, the presence of three-dimensional RGO interfaces and bifunctional nickel nanoparticles substantially influences the related physical properties in the resulting hierarchical composite textiles. Eletromagnetic interference (EMI) shielding performance suggests that the hierarchical composite textiles hold a strong shielding effectiveness greater than 61 dB, showing greater advantages than conventional polymeric and foamy shielding composites. As a polymer-free lightweight structure, flexible CF-RGO-Ni composites of all electromagnetic active components offer unique understanding of the multi-scale and multiple mechanisms in electromagnetic energy consumption. Such a novel prototype of shielding structures along with convenient technology highlight a strategy to achieve high-performance EMI shielding, coupled with a universal approach for preparing advanced lightweight composites with graphene interfaces. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C7H8N2O3, contains a 1:1 mixture of two tautomers, viz. ethyl 6-oxo-1,6-dihydro­pyrimidine-5-carboxyl­ate and ethyl 4-oxo-1,4-dihydro­pyrimidine-5-carboxyl­ate. The mol­ecules are linked into a three-dimensional network by N—H⋯O, C—H⋯O and C—H⋯N hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title compound, C12H10F3N3O2S, the molecules are linked into two-dimensional networks parallel to (1 0) through a mixture of π–π stacking and N—H...N hydrogen-bond interactions. [ABSTRACT FROM AUTHOR]

The mol­ecule of the title compound, C14H28N2O4P2S2, possesses a crystallographically imposed inversion centre. The mol­ecular structure is stabilized by two C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]