《Enantioconvergent Cu-Catalyzed Intramolecular C-C Coupling at Boron-Bound C(sp3) Atoms of α-Aminoalkylboronates Using a C1-Symmetrical 2,2′-Bipyridyl Ligand Attached to a Helically Chiral Macromolecular Scaffold》 was published in Journal of the American Chemical Society in 2020. These research results belong to Yoshinaga, Yukako; Yamamoto, Takeshi; Suginome, Michinori. Formula: C6H6BrN The article mentions the following:
Enantioconvergent intramol. coupling of α-(2-bromobenzoylamino)benzylboronic esters was achieved using a copper catalyst having helically chiral macromol. bipyridyl ligand, PQXbpy. Racemic α-(2-bromobenzoylamino)benzylboronic esters were converted into (R)-configured 3-arylisoindolinones with high enantiopurity using right-handed helical PQXbpy as a chiral ligand in a toluene/CHCl3 mixed solvent. When enantiopure (R)- and (S)-configured boronates were sep. reacted under the same reaction conditions, both afforded (R)-configured products through formal stereoinvertive and stereoretentive processes, resp. From these results, a mechanism involving deracemization of organocopper intermediates in the presence of PQXbpy is assumed. PQXbpy switched its helical sense to left-handed when a toluene/1,1,2-trichloroethane mixed solvent was used, resulting in the formation of the corresponding (S)-products from the racemic starting material. In the part of experimental materials, we found many familiar compounds, such as 2-Bromo-5-methylpyridine(cas: 3510-66-5Formula: C6H6BrN)
2-Bromo-5-methylpyridine(cas: 3510-66-5) belongs to pyridine. In industry and in the lab, pyridine is used as a reaction solvent, particularly when its basicity is useful, and as a starting material for synthesizing some herbicides, fungicides, and antiseptics.Formula: C6H6BrN