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A nickel-catalyzed reductive cross-electrophile coupling between the redox-active N-trifluoroethoxyphthalimide and iodoarenes is documented. The protocol reproduces a formal arylation of trifluoroacetaldehyde under mild conditions in high yields (up to 88 %) and with large functional group tolerance (30 examples). A combined computational and experimental investigation revealed a pivotal solvent assisted 1,2-Hydrogen Atom Transfer (HAT) process to generate a nucleophilic α-hydroxy-α-trifluoromethyl C-centered radical for the Csp 2 -Csp 3 bond forming process., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

We present an environmentally benign methodology for the covalent functionalization (arylation) of reduced graphene oxide (rGO) nanosheets with arylazo sulfones. A variety of tagged aryl units were conveniently accommodated at the rGO surface via visible-light irradiation of suspensions of carbon nanostructured materials in aqueous media. Mild reaction conditions, absence of photosensitizers, functional group tolerance and high atomic fractions (XPS analysis) represent some of the salient features characterizing the present methodology. Control experiments for the mechanistic elucidation (Raman analysis) and chemical nanomanipulation of the tagged rGO surfaces are also reported., (© 2022 Wiley-VCH GmbH.)

Graphene oxide (GO) is experiencing growing interest by synthetic organic chemists as a promoter of chemical transformations. The synergistic role of the multiple functionalities featuring the nanostructured carbon materials and their π-domains enables the interplay of specific activation modes towards organic compounds that can explore unprecedented chemical modifications. A detailed comprehension of the mechanistic details that govern the transformations guided by GO is a not fully solved task in the field. In this direction, more sophisticated and diversified techniques are employed, providing insights towards intriguing activation modes exerted by the π-matrix and the oxygenated/sulfonate groups decorating the functionalized nano-carbon material. The present Minireview accounts for a critical survey of the most recent developments in the area of GO-mediated organic transformations with a specific focus on mechanist aspects., (© 2020 Wiley-VCH GmbH.)

The site-selective allylative and allenylative dearomatization of indoles with alcohols was performed under carbocatalytic regime in the presence of graphene oxide (GO, 10 wt % loading) as the promoter. Metal-free conditions, absence of stoichiometric additive, environmentally friendly conditions (H 2 O/CH 3 CN, 55 °C, 6 h), broad substrate scope (33 examples, yield up to 92 %) and excellent site- and stereoselectivity characterize the present methodology. Moreover, a covalent activation model exerted by GO functionalities was corroborated by spectroscopic, experimental and computational evidences. Recovering and regeneration of the GO catalyst through simple acidic treatment was also documented., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)