4,4 ‘,4 ”-Trimethy1-2,2 ‘:6 ‘,2 ”-terpyridine by Oxidative Coupling of 4-Pico line

Robo, M., M. Prinsell, and D. Weix. 4,4 ‘,4 ”-Trimethy1-2,2 ‘:6 ‘,2 ”-Terpyridine by Oxidative Coupling of 4-Pico Line. J. Org. Chem., 2008.
Abstract Alkylated terpyridine ligands are an increasingly important component of catalysis and dyes but are costly because their synthesis is challenging and often low-yielding. We report an improved method for the Pd/C-catalyzed dehydrogenative coupling of 4-picoline to form the bi- and terpyridine. The addition of MnO2 improves the yield of the reaction, making the reaction useful on a large scale (up to 200 mmol). The use of Pd(OAc)(2) or Pd/C/pivalic acid leads to the selective formation of bipyridine.
Keywords 2,2′-bipyridines2,2’/6′,2”-terpyridinesactivated metal catalystsalkyl electrophilescomplexesderivativespyridinesrutheniumsubstituted terpyridinessynthetical applications
DOI 10.1021/jo501925s