As part of an effort to exploit the Pd[0]-catalyzed Ullmann cross-coupling reaction in the development of a new method for the synthesis of quinolines we required access to the beta-bromoenones 10-12.Compound 11 has been reported previously but a multi-step and atom-inefficient reaction sequence is involved and,consequently,this was not suitable for our purposes.On the other hand,the iodinated counterparts of targets 10 and 11 have been prepared in a straightforward manner by Piers and co-workers through reaction of the relevant 2-(hydrox-ymethylene)cycloalkanone,viz.compound 5 or 6,with triphenylphosphine/molecular iodine in HMPA/acetonitrile/triethylamine mixtures at room temperature.
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