Rh(ii)/phosphine-cocatalyzed synthesis of dithioketal derivatives from diazo compounds through simultaneous construction of two different C-S bonds.

Rhodium(ii)/phosphine-cocatalyzed bis-sulfuration of α-diazocarbonyl compounds using thiosulfonates as the sulfenylating agent, which provided two sulfur-containing moieties, was developed via simultaneous inter- and intra-molecular C-S bond formation. This novel protocol provides a rapid synthetic route to dithioketal derivatives in moderate to good yields in an atom-economic process. The transformation is proposed to proceed through phosphine ylide formation followed by S(O2)-S bond cleavage and rearrangement.

Merging gold catalysis, organocatalytic oxidation, and Lewis acid catalysis for chemodivergent synthesis of functionalized oxazoles from N-propargylamides.

Novel catalytic systems consisting of cationic gold complexes, N-hydroxyphthalimide (NHPI), and transition-metal-based Lewis acids have been developed for the one-pot synthesis of functionalized oxazoles from N-propargylamides with excellent functional group tolerance. These transformations demonstrated the excellent compatibility of homogeneous gold catalysis with organocatalytic oxidative carbon-nitrogen bond formations using tert-butyl nitrite as the terminal oxidant. Moreover, oxazolecarbonitriles or carboxamides can be easily synthesized in a one-pot protocol according to the different synthetic requirements.

Cu-Catalyzed Synthesis of 3-Formyl Imidazo[1,2-a]pyridines and Imidazo[1,2-a]pyrimidines by Employing Ethyl Tertiary Amines as Carbon Sources.

A highly efficient synthesis of 3-formyl imidazo[1,2-a]pyridine and imidazo[1,2-a]pyrimidine, under Cu-catalyzed aerobic oxidative conditions and by utilizing ethyl tertiary amines as carbon sources, is disclosed. A novel activation mode of ethyl tertiary amines in which simultaneous selective cleavage of C-C bond and C-N bond of ethyl group with molecular oxygen as terminal oxidant in this one-pot protocol is reported for the first time. This reaction features broad substrate scope, good functional group tolerance, as well as diversified and valuable products.

Z-Selective Synthesis of γ,δ-Unsaturated Ketones via Pd-Catalyzed Ring Opening of 2-Alkylenecyclobutanones with Arylboronic Acids.

Pd-catalyzed 1,2-addition (instead of 1,4-addition) of arylboronic acids to 2-alkylenecyclobutanones followed by ß-carbon elimination from the resulting palladium cyclobutanolates to afford γ,δ-unsaturated ketones was developed. The desired γ,δ-unsaturated ketones were obtained in good to excellent yields with Z/E selectivities of up to >99:1 and a broad spectrum of functional group tolerability.

Substituent-Controlled Chemoselective Cleavage of C═C or Csp(2)-C(CO) Bond in α,ß-Unsaturated Carbonyl Compounds with H-Phosphonates Leading to ß-Ketophosphonates.

An unprecedented substituent-controlled chemoselective cleavage of C═C double bond or C(sp(2))-C(CO) bond along with aerobic phosphorylation of α,ß-unsaturated carbonyl compounds with H-phosphonates through a radical process has been disclosed. The current strategy provides an access to ß-ketophosphonates under mild conditions with a wide substrate scope.