Synthesis of Azulen-1-yl Ketones via Oxidative Cleavage of C–C Multiple Bonds in <i>N</i>‑Sulfonyl Enamides and 1‑Alkynes under Air and Natural Sunlight

A synthetic method to prepare azulen-1-yl ketones was developed via oxidative cleavage of the C–C double bond in the reaction of easily obtainable <i>N</i>-sulfonyl enamides with Cs₂CO₃ under air and natural sunlight and in the absence of a photosensitizer. Oxidative cleavage of C–C triple bonds was also demonstrated for the synthesis of azulen-1-yl ketones via a tandem Cu-catalyzed [3 + 2] cycloaddition, Rh-catalyzed arylation, photooxygenation, and ring-opening reaction in one pot under air and natural sunlight

Phosphaannulation by Palladium-Catalyzed Carbonylation of C–H Bonds of Phosphonic and Phosphinic Acids

An efficient phosphaannulation by Pd-catalyzed carbonylation of C–H bonds of phosphonic and phosphinic acids for the synthesis of oxaphosphorinanone oxides is reported. These compounds are novel phosphorus heterocyclic scaffolds, thus opening a new avenue to sequential C–C/C–O bond formation in one pot

Synthesis of Cinnolin-3(2<i>H</i>)‑one Derivatives from Rh-Catalyzed Reaction of Azobenzenes with Diazotized Meldrum’s Acid

A synthetic method of a wide range of cinnolin-3­(2<i>H</i>)-one derivatives is developed from the reaction of symmetrical as well as unsymmetrical azobenzenes with diazotized Meldrum’s acid <i>via</i> Rh-catalyzed C–H alkylation followed by cyclization

Synthesis of Cinnolin-3(2<i>H</i>)‑one Derivatives from Rh-Catalyzed Reaction of Azobenzenes with Diazotized Meldrum’s Acid

A synthetic method of a wide range of cinnolin-3­(2<i>H</i>)-one derivatives is developed from the reaction of symmetrical as well as unsymmetrical azobenzenes with diazotized Meldrum’s acid <i>via</i> Rh-catalyzed C–H alkylation followed by cyclization

Synthesis of Cinnolin-3(2<i>H</i>)‑one Derivatives from Rh-Catalyzed Reaction of Azobenzenes with Diazotized Meldrum’s Acid

A synthetic method of a wide range of cinnolin-3­(2<i>H</i>)-one derivatives is developed from the reaction of symmetrical as well as unsymmetrical azobenzenes with diazotized Meldrum’s acid <i>via</i> Rh-catalyzed C–H alkylation followed by cyclization

Synthesis of 1,2-Benzothiazines by a Rhodium-Catalyzed Domino C–H Activation/Cyclization/Elimination Process from <i>S</i>‑Aryl Sulfoximines and Pyridotriazoles

A method for the synthesis of a large number of 1,2-benzothiazines bearing pyridyl as well as carbonyl groups is developed from rhodium-catalyzed carbene insertions into aromatic C–H bonds of <i>S</i>-aryl sulfoximines using pyridotriazoles by denitrogenative cyclization followed by the elimination of alcohols. The present method involves the N–H/C–H activation of simple alkyl aryl sulfoximines and has the advantages of a broad substrate scope, high functional group tolerance, and good regioselectivity

Synthesis of 2‑Aryl‑2<i>H</i>‑benzotrizoles from Azobenzenes and <i>N</i>‑Sulfonyl Azides through Sequential Rhodium-Catalyzed Amidation and Oxidation in One Pot

An efficient synthetic method of 2-aryl-2<i>H</i>-benzotriazoles from nonprefunctionalized azobenzenes and <i>N</i>-sulfonyl azides via sequential Rh-catalyzed amidation (C–N bond formation) and oxidation (N–N bond formation) with PhI­(OAc)₂ in one pot is reported

Synthesis of Fluorenes via Tandem Copper-Catalyzed [3 + 2] Cycloaddition and Rhodium-Catalyzed Denitrogenative Cyclization in a 5-<i>Exo</i> Mode from 2‑Ethynylbiaryls and <i>N</i>‑Sulfonyl Azides in One Pot

An efficient synthetic method of fluorenes having an enamine moiety at C-9 methylene bridge is developed from <i>N</i>-sulfonyl-4-biaryl-1,2,3-triazole derivatives via Rh-catalyzed denitrogenative cyclization in a 5-<i>exo</i> mode. Rh-catalyzed denitrogenative cyclization followed by catalytic hydrogenation produces <i>N</i>-tosylaminomethyl-substituted fluorenes in one pot. Moreover, fluorenes are synthesized via tandem Cu-catalyzed [3 + 2] cycloaddition and Rh-catalyzed denitrogenative cyclization in a 5-<i>exo</i> mode starting from 2-ethynylbiaryls and <i>N</i>-sulfonyl azides in one pot