Synthesis of C₂-Symmetric Benzimidazolium Salts and Their Application in Palladium-Catalyzed Enantioselective Intramolecular α-Arylation of Amides.
A series of C₂-symmetric chiral benzimidazolium salts, the precursor of N-heterocyclic carbene ligands, were designed and synthesized from 1,2-dibromobenzene. In situ prepared corresponding carbenes were tested in the asymmetric palladium-catalyzed intramolecular α-arylation of amides, affording chiral diarylmethanols with high yields and moderate enantioselectivities.
['He|Weiping|W|', 'Zhao|Wei|W|', 'Zhou|Bihui|B|', 'Liu|Haifeng|H|', 'Li|Xiangrong|X|', 'Li|Linlin|L|', 'Li|Jie|J|', 'Shi|Jianyou|J|']
D000577:Amides D000779:Anesthetics, Local D001969:Bromobenzenes D002384:Catalysis D007211:Indoles D008697:Methane D010165:Palladium D012492:Salts D013237:Stereoisomerism
benzimidazolium N-heterocyclic carbene Pd-catalyzed asymmetric intramolecular α-arylation