Enantioselective Ruthenium(II)-Catalyzed Access to Benzonorcaradienes by Coupling of Oxabenzonorbornadienes and Alkynes
作者:Sung Hwan Park、Shou-Guo Wang、Nicolai Cramer
DOI:10.1021/acscatal.9b03858
日期:2019.11.1
methods to access benzonorcaradiene enantioselectively are very scarce. We disclose an enantioselective ruthenium(II)-catalyzed synthesis of benzonorcaradiene by coupling of oxabenzonorbornadienes and alkynes. An easily accessible chiral cyclopentadienyl ligand (Cpx) provides access to exo-benzonorcaradiene in exclusive diastereoselectivity and with enantioselectivities of up to 97.5:2.5 er. Mechanistically
Ruthenium-Catalyzed Coupling of Oxabenzonorbornadienes with Alkynes Bearing a Propargylic Oxygen Atom: Access to Stereodefined Benzonorcaradienes
作者:Alphonse Tenaglia、Sylvain Marc、Laurent Giordano、Innocenzo De Riggi
DOI:10.1002/anie.201104589
日期:2011.9.19
Stereodefined: The title reaction provides an atom‐economic route to benzonorcaradienes. The diastereoselectivity of the coupling relies upon the structure of the alkene; unsubstituted bicyclic alkenes afforded exclusively exo‐benzonorcaradienes (see scheme) whereas the bicyclic alkenes with substituents at the bridgehead positions resulted in endo‐benzonorcaradienes.