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A rhodium(III)‐catalyzed C−H activation/[4+1] annulation of 2‐aryl‐3H‐indoles and CF3‐substituted imidoyl sulfoxonium ylides (TFISYs) has been achieved, producing a wide variety of trifluoroacetimidoyl‐substituted 11H‐isoindolo[2,1‐a]indoles in 51–86% yields. The cascade reaction involves C−H imidoylmethylation, tautomerization and AgOAc‐mediated C−N bond formation sequence. The reaction could be scaled up to 2 mmol scale. [ABSTRACT FROM AUTHOR]

A heating‐induced desulfuration annulation of pyridinium 1,4‐zwitterionic thiolates and CF3‐substituted imidoyl sulfoxonium ylides has been achieved, allowing a route to biologically important 5‐trifluoromethylpyrroles. The transformation proceeds through an unusual ((3+3)‐1) pathway under metal‐free conditions with the extrusion of 4‐methoxypyridine, sulfur and DMSO. The scale‐up reaction and further transformation of the obtained pyrrole products have been performed to demonstrate the synthetic utility of the developed method. [ABSTRACT FROM AUTHOR]

An approach for the construction of 5‐trifluoromethyl‐1,4‐dihydro‐1,2,4‐triazines has been developed via base‐mediated [3+3] cycloaddition of in‐situ generated nitrile imines and CF3‐substituted imidoyl sulfoxonium ylides. The metal‐free protocol is characterized by readily available starting materials, mild conditions, a broad substrate scope, high efficiency, good synthetic prospect, and scalability. [ABSTRACT FROM AUTHOR]

Employing anilines as nucleophiles in double carbonylation is a longstanding challenge. In this communication, a Mn(III)‐promoted double carbonylation of alkylborates or Hantzsch esters with anilines toward the synthesis of α‐ketoamides has been developed. By using easily available potassium alkyltrifluoroborates or Hantzsch esters as the starting material, and cheap and non‐toxic Mn(OAc)3 ⋅ 2H2O as the promotor, a broad range of alkyl α‐ketoamide derivatives were synthesized in moderate to good yields with excellent selectivity. [ABSTRACT FROM AUTHOR]

A procedure on palladium‐catalyzed carbonylative reaction of trifluoroacetimidoyl chlorides and nitro compounds for the construction of pharmaceutically valuable 2‐(trifluoromethyl)quinazolin‐4(3H)‐ones has been achieved. In this transformation, Mo(CO)6 has been used both as a convenient CO source and a reducing reagent. This newly developed protocol is compatible with various nitro compounds and can be readily scaled up to 1 mmol scale. [ABSTRACT FROM AUTHOR]

A low cost FeCl3‐mediated cascade annulation of trifluoroacetimidoyl chlorides and hydrazides for the efficient synthesis of 5‐trifluoromethyl‐1,2,4‐triazoles has been developed. The transformation proceeds through a cascade base‐promoted intermolecular C−N bond formation and FeCl3‐mediated intramolecular dehydration sequence under mild conditions. The protocol exhibits many notable features and can be readily scaled up to gram scale. [ABSTRACT FROM AUTHOR]

A formal condensation and [4+1] annulation reactions of 3‐isothiocyanato oxindoles with aza‐o‐quinone methides have been reported in this paper for the first time. The use of Na2CO3 as a base exclusively gave the corresponding condensed products in good yields, which can be smoothly transformed into the formal [4+1] annulation products if using DBU as a base. In addition, isothiocyanate could serve as a leaving group during the nucleophilic addition reaction has been disclosed. The two bases play different roles in the reaction and the desired cyclized products can be also obtained in good to high yields in a one‐pot manner under mild conditions. [ABSTRACT FROM AUTHOR]

Herein, we developed a copper‐catalyzed approach for the remote C(sp3)−H alkynylation of N‐fluoro‐sulfonamides. With Cu(OTf)2 as the catalyst, the carbon radical which generated from nitrogen radical‐mediated 1,5‐hydrogen atom transfer, go through an addition/fragmentation reaction with various acetylene sulfones. A variety of internal alkynes were synthesized in high yield and regioselectivity. Notably, celecoxib‐derived substrate can also gave the corresponding functionalized product in good yield under the standard conditions. [ABSTRACT FROM AUTHOR]

Quinolin-2(1 H)-ones are important chemicals with various applications in pharmaceuticals. In this communication, we have developed a novel and efficient iridium-catalyzed carbonylative annulation of simple anilines with internal alkynes for the straightforward synthesis of halogen-containing quinolin-2(1 H)-ones. The reaction proceeds without preactivation and directing groups through direct N-H and C-H bond activation with a broad substrate scope and high efficiency. Halogen functional groups can be well tolerated here. Remarkably, this is the first example of an iridium-catalyzed carbonylative C-H activation of anilines. [ABSTRACT FROM AUTHOR]

Herein a practical and efficient protocol for preparing a range of aminoisoquinolines is reported. Various aminoisoquinolines were prepared in moderate to good yields from the corresponding 2-methylbenzonitriles and benzonitriles upon treatment with potassium tert-butoxide. [ABSTRACT FROM AUTHOR]

An interesting protocol for the synthesis of N-(2-pyridyl)indoles based on a palladium@cerium(IV) oxide-catalyzed oxidative CH activation reaction has been developed. By using alkynes and N-phenylpyridin-2-amines as substrates, the corresponding indoles were isolated in moderate to excellent yields. Notably, palladium@cerium(IV) oxide showed better activity compared with other tested commercially available heterogeneous catalysts and only catalytic amounts of copper(II) salt and air as co-oxidant were required here. [ABSTRACT FROM AUTHOR]