A highly efficient and convenient procedure for straightforward synthesizing structurally diverse 3-benzofurylsubstituted phthalides is developed with moderate to excellent yields via cyclization reactions of benzofurans with 2-carbonyl-benzoic acid. The reaction features readily available starting materials, a broad scope, and a high atom economy. Besides, an interesting regioselective was observed in some cases.

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An overview of the recent advancements in the synthesis of benzo [d]isothiazoles is provided. The synthetic approaches developed between 2010 and October 2023 are discussed and arranged in five categories according to the substrate used for the scaffold assembly. The novel synthetic methodologies contribute to the enlargement of the chemical space occupied by benzo [d]isothiazoles and to the exploration of its applications in various fields such as medicinal chemistry and catalysis.

A straightforward entry to 5-membered cyclic cyanamides from readily available allylic and propargylic cyanamides is reported. These starting materials are easily obtained by a multicomponent A3 coupling followed by a von Braun reaction and they were shown to be readily cyclized by a ring-closing enyne metathesis, upon simple reaction with Grubbs II catalyst, to the corresponding highly functionalized cyclic cyanamides.

Herein, we demonstrate the viability of late-stage diversification of 4-arylphthalazin-1(2H)-one through iridium-catalyzed C-H bond amidation. These are an important class of heterocycles owing to their pharmacological potential. Notably, the amidation was conducted with excellent regioselectivity, and the mono-/diamidated products were obtained in good to high yields by simply controlling the ratio of substrates, respectively. This protocol features operational simplicity, a broad substrate scope, and good functional group tolerance.