Enantiomerically pure S-5-hydroxy-2-piperidinone 4, readily available from S-glutamic acid, serves as a key intermediate for the synthesis of 3,4-trans substituted piperidine derivatives. The substituents in the 4-position are introduced via 1,4 conjugate organocuprate addition to 7 with excellent trans selectivity. This reaction is employed for the synthesis of a paroxetine analogue 21g. All attempts to transform 16 to (+)-meroquinene 17 failed.