attacked by arene nucleophiles with high facial diastereoselectivity (dr >/= 94/6). Benzylic cations, such as 2, were generated under acidic conditions and reacted with arenes in intra- and intermolecular Friedel-Crafts alkylation reaction. The depicted reaction 1 --> 3 represents one example for the unprecedented, highly diastereoselectiveintermolecular Friedel-Crafts alkylation reactions which were
Diastereoselective Friedel-Crafts Cyclization Reactions to 2-Substituted 1-Phenyl-1,2,3,4-tetrahydronaphthalenes
作者:Thorsten Bach、Friedrich Mühlthau
DOI:10.1055/s-2005-918482
日期:——
almost perfect diastereoselectivity (dr >95:5). For the cyclizationreaction to tetralins (five examples) trifluoromethane sulfonic acid proved to be the reagent of choice (91-98% yield). The diastereoselectivecyclization of epoxide 2-phenethyl-3-phenyloxirane to trans-1,2,3,4-tetrahydro-l-phenylnaphth-2-ol was accompanied by side reactions and the yield was lower (45%). The reactions occurred stereoconvergently