Kwak, Se Hun published the artcileN-Aminopyridinium Ylide-Directed, Copper-Promoted Amination of sp2 C-H Bonds, Quality Control of 1877-71-0, the publication is Journal of Organic Chemistry (2019), 84(20), 13022-13032, database is CAplus and MEDLINE.
N-Aminopyridinium ylides were used as monodentate directing groups for copper-promoted C-H/N-H coupling of sp2 C-H bonds with pyrazoles, imidazoles, and sulfonamides. Reactions proceed in fluorinated alc. solvents at elevated temperatures and require use of 1.3-3 equiv of copper(II) acetate. This appears to be the first method for copper-promoted C-H/N-H coupling directed by a removable monodentate auxiliary in absence of added ligands.
Journal of Organic Chemistry published new progress about 1877-71-0. 1877-71-0 belongs to esters-buliding-blocks, auxiliary class Carboxylic acid,Benzene,Ester, name is 3-(Methoxycarbonyl)benzoic acid, and the molecular formula is C9H8O4, Quality Control of 1877-71-0.
Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics