Norbornanoid Chiral Ketones by Desymmetrization of Dibromoalkenes |
| |
| Authors: | Ramazan Koçak Giuseppe Borsato Ottorino De Lucchi Arif Daştan |
| |
| Affiliation: | 1. Ataturk University, Science Faculty, Department of Chemistry, TR‐25240, Erzurum, (phone: +90‐442‐2314405;2. fax: +90‐442‐2360948);3. Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari di Venezia, Dorsoduro 2137, I‐30123 Venezia |
| |
| Abstract: | New optically active polycyclic ketones 6a – 6d , amenable to a large variety of synthetic applications, have been prepared from readily available 2,3‐dibromonorbornene and analogs (Scheme 2) via desymmetrization with (?)‐ephedrine, followed by hydrolysis under mild acidic conditions. At variance with substrates 4a – 4d , the sterically hindered norbornene derivative 4e reacts with the solvent N‐methylpyrrolidin‐2‐one (NMP) leading to the formation of the unusual cyclopropanoid products 8a and 8b . |
| |
| Keywords: | Norbornanes (− )‐Ephedrine Desymmetrization Ketones, chiral Norbornenones, chiral Benzonorbornadiene Oxazolidine Enantioselectivity |
|
|
