THE MICHAEL-TYPE ADDITION-REACTION - A STEREOCONTROLLED CONSTRUCTION OF A NEW QUATERNARY CHIRAL CENTER AT C(2) OF 2-(4-HYDROXYBENZYL)CYCLOHEXANONE DERIVATIVES

The Michael-type addition reaction was used as a convenient method for the stereocontrolled construction of a new quaternary C-center at pos ition 2 of 2-substituted cyclohexanones (Scheme) with the aim to study the effect of an additional substituent at C(2) in a series of biolog ically active compounds bearing generally a 2-substituted cyclohexanon e moiety. Thus, a new series of compounds consisting of a racemate (RS )-12 and its enantiomers (S)- and (R)-12 (ee greater than or equal to 96% for both enantiomers) was obtained. The Michael adduct derivatives (S)-, (R)-, and (RS)-12 were subjected to a biological screening usin g several non-related insect species.