In 2022,Wolinska, Ewa; Rozbicki, Przemyslaw; Branowska, Danuta published an article in Monatshefte fuer Chemie. The title of the article was 《Chiral pyridine oxazoline and 1,2,4-triazine oxazoline ligands incorporating electron-withdrawing substituents and their application in the Cu-catalyzed enantioselective nitroaldol reaction》.Formula: C5H3Br2N The author mentioned the following in the article:
Eight pyridine-containing and four 1,2,4-triazine-containing chiral oxazoline ligands incorporating electron-withdrawing substituents have been oxazolines I (R1 = Ph, t-Bu; R2 = H, F; R3 = H, Cl; R4 = H, F, Cl, nitro; R5 = H, Br), II and III synthesized by two-step route including Buchwald-Hartwig amination. Enantio-inducing activity of the ligands has been assessed in the copper-catalyzed asym. nitroaldol reactions and the influence of the electron-withdrawing substituents on the ligands’ activity has been investigated. In the experiment, the researchers used 2,6-Dibromopyridine(cas: 626-05-1Formula: C5H3Br2N)
2,6-Dibromopyridine(cas: 626-05-1) belongs to pyridine. When pyridine is adsorbed on oxide surfaces or in porous materials, the following species are commonly observed: (i) pyridine coordinated to Lewis acid sites, (ii) pyridine H-bonded to weakly acidic hydroxyls, and (iii) protonated pyridine. At high coverage, physisorbed pyridine and protonated dimers can also be observed.Formula: C5H3Br2N