The reaction of N-unprotected methylesters of phenylglycine derivatives (1a–1f) with electron-rich internal alkynes (2a–2e), catalyzed by [Ru(cymene)Cl] (10%), gives the corresponding 3,4-disubstituted isoquinoline-1-carboxylates 3 through C[sbnd]H/N[sbnd]H oxidative coupling. The C[sbnd]H bond activation step is assisted by carboxylates, and N-fluoro-2,4,6-trimethylpyridinium triflate works as the terminal oxidant. The process shows a remarkable tolerance to the presence of diverse electron-releasing and electron-attracting functional groups at the phenyl ring of the amino acid. In addition, the reaction of phenylglycine derivatives (1a–1f) with methyl acrylate (4a) catalyzed by [Ru(cymene)Cl] (10%) under the same experimental conditions, gives the corresponding 3,N-disubstituted isoindoline-1-carboxylates 5 through C[sbnd]H/N[sbnd]H coupling. Isoindolines 5 are obtained as a mixture of diastereoisomers, with moderate to high values of diastereomeric excess (up to 80%).

Funding by the Ministerio de Economia y Competitividad (MINECO) (Spain, Project CTQ2013-40855-R) and Gobierno de Aragón-Fondo Social Europeo (Spain, groups E40 and E97) is gratefully acknowledged. S.R. thanks Gobierno de Aragón for a PhD grant.

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