Palladium(II)-Catalyzed Ortho Arylation of 2-Phenoxypyridines with Potassium Aryltrifluoroborates via C-H Functionalization was written by Chu, Jean-Ho;Lin, Pi-Shan;Wu, Ming-Jung. And the article was included in Organometallics in 2010.Safety of 2-Phenoxypyridine This article mentions the following:
An efficient synthesis of ortho-arylated 2-phenoxypyridines catalyzed by Pd acetate is described. Treatment of 2-phenoxypyridines with two and a half equivalent of K aryltrifluoroborate and 10 mol % of Pd(OAc)2 in the presence of two equivalent of Ag2CO3, one equivalent of p-benzoquinone (BQ), and four equivalent of DMSO with (or without) H2O at 130-140° for 48 h in dried CH2Cl2 gave the ortho-arylated 2-phenoxypyridines in modest to excellent yields. P-Benzoquinone is an important ligand and cooxidant for the transmetalation reductive elimination step in the catalytic reaction. The study of kinetic isotope effect (kH/kD) is 5.25, which indicates that C-H bond cleavage occurs in the rate-determining step. One of the arylated compounds, 2-(4′-nitrobiphenyl-2-yloxy)pyridine, was treated with Me trifluoromethanesulfonate and subsequently Na methoxide to give the 2-(4-nitrophenyl)phenol in 79% yield, demonstrating that pyridine is a removable directing group. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0Safety of 2-Phenoxypyridine).
2-Phenoxypyridine (cas: 4783-68-0) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Safety of 2-Phenoxypyridine