Enantioselective Synthesis of Atropisomeric Vinyl Arene Compounds by Palladium Catalysis: A Carbene Strategy

• Published in: Angewandte Chemie International Edition Vol. 55; no. 6; pp. 2186 - 2190
• Main Authors: Feng, Jia, Li, Bin, He, Yun, Gu, Zhenhua
• Format: Journal Article
• Language: English
• Published: WEINHEIM Blackwell Publishing Ltd 05.02.2016; Wiley; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Aromatic compounds; Asymmetric synthesis; biaryls; Bromides; Catalysis; Chemical synthesis; Chemistry; Chemistry, Multidisciplinary; chirality; Enantiomers; enantioselectivity; Hydrazones; Oxides; Palladium; Phosphine; Physical Sciences; Science & Technology; enantioselectivity; chirality; NATURAL-PRODUCTS; EFFICIENT SYNTHESIS; 2+2+2 CYCLOADDITION; C-H ACTIVATION; DYNAMIC KINETIC RESOLUTION; N-TOSYLHYDRAZONES; ASYMMETRIC SUZUKI-MIYAURA; CROSS-COUPLING REACTIONS; AXIALLY CHIRAL BIARYLS; biaryls; ARYL HALIDES; palladium; hydrazones
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201509571

An efficient palladium‐catalyzed asymmetric synthesis of axially chiral vinyl arenes from aryl bromides and hydrazones is reported. The products were easily oxidized to axially chiral biaryl compounds, and the phosphine oxides were readily reduced to phosphine ligands. With a twist: An enantioselective palladium‐catalyzed synthesis of atropisomeric vinyl arenes from aryl bromides and hydrazones is reported. The use of hydrazone precursors as coupling partners resulted in mild reaction conditions, and thus a broad functional‐group tolerance. The products were isolated with ee values of up to 97 %. Ts=4‐toluenesulfonyl.