Multiple Paths for Photo-methylation and -methoxylation of Methyl 2-Pyridinecarboxylate in Methanol

Article abstract of DOI:10.1246/bcsj.54.3785

UV-irradiation of methyl 2-pyridinecarboxylate in methanol in the absence of added acid brings about methylation at the 5-position via the excitation of C=O of the ester group, while in the presence of added acid the 4-position of the pyridine ring is methylated.In the presence of sulfuric acid methoxylation via an excimer is dominant over methylation.In the presence of hydrochloric acid methylation via chlorine atoms becomes dominant.