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The use of aliphatic amines as alkylating reagents in organic synthesis via C–N bond activation remains underdeveloped. We herein describe a novel ruthenium-catalysed and directing-group assisted protocol for the synthesis of meta-alkylated arenes via dual C–H and C–N activation. Bench-stable and easily handled redox-active Katritzky pyridinium salts derived from abundant amines and amino acid species were used as alkyl radical precursors. This catalytic reaction could accommodate a broad range of functional groups and provide access to various meta-alkylated products.

An efficient and mild three-component cyanofluorination of vinyl ethers with Selectfluor and TMSCN is described. The reaction protocol is operationally simple, allowing the access to various α-alkoxy-β-fluoronitriles bearing quaternary α-carbons in good to excellent yields. The mechanistic studies indicated that the formation of an electron donor–acceptor (EDA) aggregate and a subsequent single electron transfer (SET) process might be involved in the reaction.

An efficient and mild method was developed for the synthesis of 6-alkylated phenanthridines upon visible light irradiation. Bench-stable and easily handled redox-active Katritzky pyridinium salts derived from abundant amino acids/peptides were used as radical precursors for the alkylation of isocyanobiphenyl species. The reaction displays an excellent functional group tolerance and a potential utility for peptide functionalization, allowing access to desired products in good to excellent yields.

The use of aliphatic amines as alkylating reagents in organic synthesis via C-N bond activation remains underdeveloped. We herein describe a novel ruthenium-catalysed and directing-group assisted protocol for the synthesis of meta-alkylated arenes via dual C-H and C-N activation. Bench-stable and easily handled redox-active Katritzky pyridinium salts derived from abundant amines and amino acid species were used as alkyl radical precursors. This catalytic reaction could accommodate a broad range of functional groups and provide access to various meta-alkylated products.

A regioselective cis-hydroalkylation of internal alkynes with readily prepared Katritzky pyridinium salts for the synthesis of tri-substituted alkenes is described. This reaction is the first example of a metal-catalyzed hydroalkylation of an alkyne via C-N bond activation of an amine. The reaction demonstrates broad scope and functional group tolerance, allowing access to desired products with high diversity. Preliminary mechanistic studies indicate that a combination of an SET-initiated radical process and Ni-catalyzed alkylation could engage in the reaction, which makes it possible to bypass the traditional open-shell addition pathway.

Correction for ‘Radical alkylation of isocyanides with amino acid-/peptide-derived Katritzky salts via photoredox catalysis’ by Ze-Fan Zhu, et al., Org. Biomol. Chem., 2019, 17, 1531–1534.