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Comprehensive Summary: The chemodivergent ring‐opening of cyclobutanols is described under the carbocatalytic assistance of graphene oxide (GO). The protocol enables the synthesis of diversely functionalized dienes or indenes (26 examples) based on the amount of GO employed. Spectroscopic (XPS and ssNMR) as well as experimental investigations revealed a direct involvement of the π‐domains of GO in tuning the stability of carbocationic intermediates during the reaction. [ABSTRACT FROM AUTHOR]

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 Csp2−Csp3 bond forming process. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The tandem catalytic functionalization/carboxylation of double as well as triple carbon‐carbon bonds with CO2 represent an emerging research area in synthetic organic methodology. In particular, the combination of mild reaction conditions, stoichiometric acceptor/donorless conditions (visible light photoredox catalysis) and chiral catalysts contributed to a rapid development of this intriguing research area capable of creating chemical diversity/ complexity from readily available unsaturated hydrocarbons and CO2 as a C1‐buinding block. The most recent developments in the field have been collected in the present review article and organized, based on the different sets of π‐systems/intermediates/reactive partners employed (i.e., nickelalactones, organo‐halides) as well as synthetic strategies (i.e., visible‐light photo redox catalysis). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 (H2O/CH3CN, 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. [ABSTRACT FROM AUTHOR]

The tandem catalytic functionalization/carboxylation of double as well as triple carbon‐carbon bonds with CO2 represent an emerging research area in synthetic organic methodology. In particular, the combination of mild reaction conditions, stoichiometric acceptor/donorless conditions (visible light photoredox catalysis) and chiral catalysts contributed to a rapid development of this intriguing research area capable of creating chemical diversity/ complexity from readily available unsaturated hydrocarbons and CO2 as a C1‐buinding block. The most recent developments in the field have been collected in the present review article and organized, based on the different sets of π‐systems/intermediates/reactive partners employed (i.e., nickelalactones, organo‐halides) as well as synthetic strategies (i.e., visible‐light photo redox catalysis). [ABSTRACT FROM AUTHOR]