1.
RSC Adv
; 11(30): 18162-18170, 2021 May 19.
Artigo
em Inglês
| MEDLINE
| ID: mdl-35480945
RESUMO
Amidine-based optically active resolving agents for enantiomer separation of axially chiral 1,1'-biaryl-2,2'-diols have been developed. A strongly basic amidine bearing no substituents on its nitrogen atoms enables the formation of their diastereomeric salts upon being mixed with weakly acidic phenol derivatives. Enantiopure 1,1'-biaryl-2,2'-diols can be obtained in high yields after only one crystallization of their salts with the chiral amidine derived from dehydroabietic acid. X-ray crystallography revealed that the amidine moiety forms a salt with the phenol group and additional intermolecular NH/π interactions contribute to the efficient chiral recognition process.