Lauzon, Samuel; Ollevier, Thierry published their research in Chemical Communications (Cambridge, United Kingdom) in 2021. The article was titled 《2,2′-Bipyridine-α,α’-trifluoromethyl-diol ligand: Synthesis and application in the asymmetric Et2Zn alkylation of aldehydes》.Synthetic Route of C5H3Br2N The article contains the following contents:
A chiral 2,2′-bipyridine ligand I, bearing α,α’-trifluoromethyl-alcs. at the 6,6′-positions, was designed in five steps affording either the R,R/S,S enantiomer with excellent stereoselectivities, i.e., 97% de, >99% ee and >99.5% de, >99.5% ee, resp. The key step for reaching high levels of stereoselectivity was demonstrated to be the resolution of the α-CF3-alc. using (S)-ibuprofen as the resolving agent. An initial application for the 2,2′-bipyridine-α,α’-CF3-diol ligand was highlighted in the Zn(II)-catalyzed asym. ethylation reaction of aromatic, heteroaromatic, and aliphatic aldehydes RCHO (R = 4-chlophenyl, thiophen-2-yl, Pr, etc.). Synergistic electron deficiency and steric hindrance properties of the newly developed ligand afforded the corresponding alcs. in good to excellent yields (up to 99%) and enantioselectivities (up to 95% ee). In the part of experimental materials, we found many familiar compounds, such as 2,6-Dibromopyridine(cas: 626-05-1Synthetic Route of C5H3Br2N)
2,6-Dibromopyridine(cas: 626-05-1) belongs to pyridine. Pyridine is widely used in the precursor to agrochemicals and pharmaceuticals. Also, it is used as an important reagent and organic solvent.Synthetic Route of C5H3Br2N