428874-67-3Relevant articles and documents
Synthesis of (±)-3,3′-diphenyl-2,2′-binaphthol via different routes using Pd and Ni as catalyst respectively
Fu, Zhengjiang,Cao, Xihan,Hao, Guangguo,Shi, Quanqing,Cai, Hu
, p. 831 - 836 (2020/09/09)
3,3′-Biphenyl-2,2′-binaphthols (BINOLs) are precursors of phosphoric acids that are widely used as ligands and catalysts in organic reactions. In this report, two routes for the synthesis of (±)-3,3′-diphenyl BINOLs via (±)-3,3′ bis-halogenated BINOLs int
Design of bronsted acid-assisted chiral Lewis acid (BLA) catalysts for highly enantioselective Diels-Alder reactions
Ishihara, Kazuaki,Kurihara, Hideki,Matsumoto, Masayuki,Yamamoto, Hisashi
, p. 6920 - 6930 (2007/10/03)
Bronsted acid-assisted chiral Lewis acid (BLA) was highly effective as a chiral catalyst for the enantioselective Diels-Alder reaction of both α- substituted and α-unsubstituted α,β-enals with various dienes. Hydroxy groups in optically active binaphthol derivatives and boron reagents with electron-withdrawing substituents were used as Bronsted acids and Lewis acids, respectively. Intramolecular Bronsted acids in a chiral BLA catalyst played an important role in accelerating the rate of Diels-Alder reactions and in producing a high level of enantioselectivity. In particular, excellent enantioselectivity was achieved due to intramolecular hydrogen bonding interaction and attractive π-π donor-acceptor interaction in the transition-state assembly by hydroxy aromatic groups in a chiral BLA catalyst.