2. Results and discussion
The required starting substrates 1aec were prepared via a classical
two-steps procedure involving halogenation of enones with
bromine or chlorine in anhydrous CHCl3, and subsequent dehydrohalogenation
of the intermediate dihaloderivatives by Et3N in
dry ether (Scheme 1). All of the prepared a-haloenones 1aec were
found to have the Z-configuration