posted on 2007-05-25, 00:00authored byGiuseppe Borsato, Anthony Linden, Ottorino De Lucchi, Vittorio Lucchini, David Wolstenholme, Alfonso Zambon
3-Chloronorbornenone (R)-1a (98% ee) was obtained from
trichloronorbornene 5 in two steps by the in situ generation
of dichloronorbornadiene 2a with t-BuOK and desymmetrization with (−)-ephedrine, followed by hydrolysis with
PPTS. The generality of this desymmetrization with (−)-ephedrine was tested with dibromonorbornadiene 2c and
other substituted dichloronorbornadienes.