Synthesis of azo-incorporated copolymers by C1/N2C1 copolymerization under microwave irradiation

Mechanistic studies of the copolymerization between ethyl diazoacetate and cinnamaldehyde

N^diazo,C^ω-diradical species and their chain propagation mechanism during copolymerization.

Metal-Diazo Radicals of α-Carbonyl Diazomethanes

Metal-diazo radicals of α-carbonyl diazomethanes are new members of the radical family and are precursors to metal-carbene radicals. Herein, using electron paramagnetic resonance spectroscopy with spin-trapping, we detect diazo radicals of α-carbonyl diazomethanes, induced by [Rh^ICl(cod)]₂, [Co^II(por)] and PdCl₂, at room temperature. The unique quintet signal of the Rh-diazo radical was observed in measurements of α-carbonyl diazomethane adducts of [Rh^ICl(cod)]₂ in the presence of 5,5-dimethyl-pyrroline-1-N-oxide (DMPO). DFT calculations indicated that 97.2% of spin density is localized on the diazo moiety. Co- and Pd-diazo radicals are EPR silent but were captured by DMPO to form spin adducts of DMPO-N∙ (triplet-of-sextets signal). The spin-trapping also provides a powerful tool for detection of metal-carbene radicals, as evidenced by the DMPO-trapped carbene radicals (DMPO-C∙, sextet signal) and 2-methyl-2-nitrosopropane-carbene adducts (MNP-C∙, doublet-of-triplets signal). The transformation of α-carbonyl diazomethanes to metal-carbene radicals was confirmed to be a two-step process via metal-diazo radicals.

Copolymerization of alkyl diazoacetates with α,β-unsaturated aldehydes: synthesis and application

Copolymerization of alkyl diazoacetates with α,β-unsaturated aldehydes and the product's fluorescence property.

Polymeric palladium-mediated carbene polymerization

A newly-developed metal-carbene radical polymerization mechanism is proposed for poly(imidazole-Pd)-mediated carbene polymerization, which could produce stereoregular polycarbenes besides atactic polycarbenes.

The interception of a copper-based carbene radical with an α-carbonyl diazomethane radical: C1/C1N2 copolymerization

The interception of a copper-based carbene radical with an α-carbonyl diazomethane radical affords the C1/C1N2 copolymer, which could be used as an upconversion agent.