Enantioselective Synthesis of 1,2-Benzothiazine 1-Imines via RuII /Chiral Carboxylic Acid-Catalyzed C-H Alkylation/Cyclization.

Sulfondiimines are diaza-analogues of sulfones with a chiral sulfur center. Compared to sulfones and sulfoximines, their synthesis and transformations have so far been studied to a lesser extent. Here, we report the enantioselective synthesis of 1,2-benzothiazine 1-imines, i.e., cyclic sulfondiimine derivatives from sulfondiimines and sulfoxonium ylides via C-H alkylation/cyclization reactions. The combination of [Ru(p-cymene)Cl2 ]2 and a newly developed chiral spiro carboxylic acid is key to achieving high enantioselectivity.

Rhodium(III)/Chiral Carboxylic Acid Catalyzed Enantioselective C(sp3)-H Alkylation of 8-Ethylquinolines with α,ß-Unsaturated Carbonyl Compounds.

The enantioselective C-H alkylation of 8-ethylquinolines with enones or acrolein using a RhIII catalyst and a chiral carboxylic acid is described. Under mild reaction conditions, a binaphthyl-based chiral carboxylic acid enables the enantioselective cleavage of the 8-ethylquinoline C(sp3)-H bond. The obtained results demonstrate the utility of the combination of a high-valent group 9 metal catalyst and a chiral carboxylic acid for the enantioselective C(sp3)-H activation and the subsequent C-C bond formation.

NaI-mediated divergent synthesis of isatins and isoindigoes: a new protocol enabled by an oxidation relay strategy.

A new approach for the synthesis of isatins and isoindigoes by an inexpensive and environmentally friendly NaI-mediated transformation is disclosed. The selectivity could be switched by simply varying the solvent, and isatins (using THF) and isoindigoes (using DMSO) could be obtained in moderate to excellent yields.

KI-catalyzed C-S bond formation via an oxidation relay strategy: efficient access to various α-thio-ß-dicarbonyl compounds.

An efficient and practical methodology to obtain α-thio-ß-dicarbonyl compounds was presented under alkaline conditions via potassium iodide (KI) catalysis; various symmetrical/unsymmetrical 1,3-dicarbonyl compounds were obtained under an aerobic atmosphere in moderate to excellent yields, with good functional group tolerance. Notably, a widely used anti-inflammatory drug butazodine could be modified with our protocol, even on a gram scale.