A copper-catalyzed decarboxylative disulfonylation of alkynyl carboxylic acids with sulfinic acids in aqueous solution has been developed. The reaction provides a straightforward and practical access to (E)-1,2-disulfonylethenes, which are important building blocks in synthetic organic chemistry, and exhibits a good functional group tolerance and excellent stereoselectivity. A possible mechanism for the transformation is proposed.

A novel copper-catalyzed decarboxylative oxyalkylation of alkynyl carboxylic acids with ketones and alkylnitriles via direct C­(sp3)–H bond functionalization to construct new C–C bonds and C–O double bonds was developed. This transformation is featured by wide functional group compatibility and the use of readily available reagents, thus affording a general approach to γ-diketones and γ-ketonitriles. A possible mechanism is proposed.

Figure 1. Selected bioactive pyrrolo[3,2-c]quinoline derivatives. Scheme 1. Radical-Mediated [2 + 2 + 1] Cyclization Letter pubs.acs.org/OrgLett

A practical method through a copper-catalyzed dehydrogenative coupling of carboxylic acids with H-phosphonates to construct acyl phosphate esters has been developed.

Oxidative radical cascade cyclizations of 2-cyano-3-arylaniline derived acrylamides with acetonitrile and tert-butyl peroxybenzoate have been developed to construct cyano and methyl substituted pyrido[4,3,2-gh]phenanthridines.