Ruthenium(II)-Catalyzed Chelation-Assisted Desulfitative Arylation of Benzo[h]quinolines with Arylsulfonyl Chlorides

Herein, a novel chelation-assisted C-H arylation reaction of benzo[h]quinoline is described. This transformation, using [RuCl₂(p-cymene)]₂ as the catalyst and cheap and easily accessible arylsulfonyl chlorides as the arylation source, featured simple reaction conditions, a broad substrate scope, and functional group tolerance. The successful application of some bioactive-molecule-based sulfonyl chlorides further highlighted the potential utility and importance of this desulfitative C-H arylation protocol.

Palladium-Catalysed Intermolecular Direct C–H Bond Arylation of Heteroarenes with Reagents Alternative to Aryl Halides: Current State of the Art

Abstract:

Abstract: This unprecedented review with 322 references provides a critical up-to-date picture of the Pd-catalysed intermolecular direct C–H bond arylation of heteroarenes with arylating reagents alternative to aryl halides that include aryl sulfonates (aryl triflates, tosylates, mesylates, and imidazole-1-sulfonates), diaryliodonium salts, [(diacetoxy)iodo]arenes, arenediazonium salts, 1-aryltriazenes, arylhydrazines and N’-arylhydrazides, arenesulfonyl chlorides, sodium arenesulfinates, arenesulfinic acids, and arenesulfonohydrazides. Particular attention has been paid to summarise the preparation of the various arylating reagents and to highlight the practicality, versatility, and limitations of the various developed arylation protocols, also comparing their results with those achieved in analogous Pd-catalysed arylation reactions involving the use of aryl halides as electrophiles. Mechanistic proposals have also been briefly summarised and discussed. However, data concerning Pd-catalysed direct C–H bond arylations involving the C–H bonds of aryl substituents of the examined heteroarene derivatives have not been taken into account.

Transition-metal mediated carbon-sulfur bond activation and transformations: an update

Carbon-sulfur bond cross-coupling has become more and more attractive as an alternative protocol to establish carbon-carbon and carbon-heteroatom bonds. Diverse transformations through transition-metal-catalyzed C-S bond activation and cleavage have recently been developed. This review summarizes the advances in transition-metal-catalyzed cross-coupling via carbon-sulfur bond activation and cleavage since late 2012 as an update of the critical review on the same topic published in early 2013 (Chem. Soc. Rev., 2013, 42, 599-621), which is presented by the categories of organosulfur compounds, that is, thioesters, thioethers including heteroaryl, aryl, vinyl, alkyl, and alkynyl sulfides, ketene dithioacetals, sulfoxides including DMSO, sulfones, sulfonyl chlorides, sulfinates, thiocyanates, sulfonium salts, sulfonyl hydrazides, sulfonates, thiophene-based compounds, and C[double bond, length as m-dash]S functionality-bearing compounds such as thioureas, thioamides, and carbon disulfide, as well as the mechanistic insights. An overview of C-S bond cleavage reactions with stoichiometric transition-metal reagents is briefly given. Theoretical studies on the reactivity of carbon-sulfur bonds by DFT calculations are also discussed.

C-H Sulfonylation via 1,3-Rearrangement of Sulfonyl Group in N-Protected 3-Bis-sulfonimidoindole Derivatives Using Fluorine Reagent

A C-H sulfonylation of N-protected 3-bis-sulfonimidoindole derivatives via a 1,3-rearrangement of a sulfonyl group on a bis-sulfonimide moiety using tetra-n-butylammonium fluoride (TBAF) was developed to provide 2-sulfonyl-3-sulfonamidoindole derivatives in high yields as a novel C_sp2-H functionalization of heterocycles. The rearrangement of the sulfonyl group proceeded through an intermolecular addition of the desorbed sulfinyl ion from the bis-sulfonimide moiety in the substrate.

Palladium-catalyzed successive C–H bond arylations and annulations toward the π-extension of selenophene-containing aromatic skeletons

A modular approach for the synthesis of planar π-extended selenium containing molecules from selenophene has been developed.

Visible Light-Promoted C–C Bond Formation from Hydroxyaryls in Water

An eco-friendly and direct arylation of hydroxyaryls in water using photoinduced reactions with different substrates (1-bromo-2-naphthol, 1-iodo-2-naphthol, N-(2-iodophenyl)acetamide, 5-bromouracil, 2-iodo-N-methylbenzamide, and 2-iodobenzamide) was studied. For example, π-expanded coumarins, compounds with potential optical applications, were synthesized in very high yield, without the use of toxic reagents, in a one-pot reaction. In addition, we demonstrate that the irradiation source (halogen lamp) can be efficiently replaced by an LED without altering the reaction yield.