Radical chain monoalkylation of pyridines.

The monoalkylation of -methoxypyridinium salts with alkyl radicals generated from alkenes ( hydroboration with catecholborane), alkyl iodides ( iodine atom transfer) and xanthates is reported. The reaction proceeds under neutral conditions since no acid is needed to activate the heterocycle and no external oxidant is required. A rate constant for the addition of a primary radical to -methoxylepidinium >10 M s was experimentally determined.