Tetralins (tetrahydronaphthalenes) are synthesised from benzocyclobutenols based on the rhodium-catalysed site-selective ring opening followed by intermolecular/intramolecular conjugate addition of the resulting arylrhodium species to electron-deficient alkenes. The produced structures make a remarkable contrast with those available from the same compounds under thermal reaction conditions.
Rh(I)-Catalyzed Insertion of Allenes into C–C Bonds of Benzocyclobutenols
作者:Chunliang Zhao、Li-Chuan Liu、Jing Wang、Chenran Jiang、Qing-Wei Zhang、Wei He
DOI:10.1021/acs.orglett.5b03518
日期:2016.1.15
Herein we report a Rh(I)-catalyzed two carbon insertion into C–C bonds of benzocyclobutenols by employing symmetrical and unsymmetrical allenes. This reaction provides rapid access to alkylidene tetralins bearing two adjacent stereogenic centers in good yields and diasteroselectivities.
A rhodium catalyst induced ring opening of benzocyclobutenols with selective cleavage of the C(sp(2))-C(sp(3)) bond adjacent to the hydroxyl group. The site-selectivity markedly contrasted with that of their thermal ring-opening reaction. The rhodium-catalyzed ring opening led to the development of a new alkyne insertion reaction constructing a dihydronaphthalene framework.