The sequential functionalisation of 2-phenylpyridine is presented using selective ortho- and meta-directing processes. It was found that performing a reaction sequence with meta functionalisation first followed by ortho functionalisation provided novel reaction products in good yields and with complete regioselectivity.
Reynolds, W. R., Liu, P. M., Kociok-Kohn, G., & Frost, C. G. (2013). Sequential chelation-assisted aromatic C–H functionalisation via catalytic meta sulfonation. Synlett, 24(20), 2687-2690. [ST-2013-D0836-L]. https://doi.org/10.1055/s-0033-1340011