Transition metal-catalyzed unimolecular fragment coupling (UFC) is defined as processes that forge new chemical bonds through the extrusion of molecules, such as CO and CO2, and the subsequent recombination of the remaining fragments. Herein, we report on a new UFC reaction that involves the palladium-catalyzed elimination of an isocyanate fragment from an amide, with the formation of carbon–carbon and carbon–heteroatom bonds. An organometallic intermediate that is relevant to the catalytic reaction was characterized by X-ray crystallography. This UFC reaction enables the late-stage transformation of an amide functionality, allowing amides to be used as a convertible directing or protecting group.

No abstract

The palladium-catalyzed reaction of N-allylamides bearing a tethered nucleophile results in the extrusion of an amide moiety in the form of an isocyanate with its subsequent capture by the pendant nucleophile. This reaction involves the net catalytic transposition of an amide group.

The nickel-catalyzed cross-coupling of methoxyarenes is applied to buflavine, which allows for the selective mono-substitution of one of the two methoxy groups in the molecule, leading to the formation of 2- and 3-substituted isomers. Trimethylsilylmethyl (TMSCH2), phenyl and alkynyl groups can be introduced to buflavine using this method. The resulting TMSCH2 analog of buflavine can also be converted into several other derivatives.

We report herein on the nickel-catalyzed methylation of arylphosphines using AlMe3 via the cleavage of unactivated C(aryl)–P bonds. This reaction allows for the direct, catalytic substitution of an aryl group...