SYNTHESIS OF ( <I>E</I>)- AND ( <I>Z</I>)-ISOMERS of 6-chlorohex-5-en-2-one
In this work we examined the possibility of a synthesis of stereochemically pure (5 E )- and (5 Z )-6-chlorohex-5-en-2-ones, the potential block synthones for various biologically active compounds based on the ethyl (4 E )- and ethyl (4 Z )-2-acetyl-5-chloropent-4-enoates decarbo-xylation. The decarboxylation in water-alcohol solution (1:2) of KOH during 20 min at 50 <sup>о</sup>С gives corresponding main products in 75 and 80% yields and aldols less than 1-3 % yield.