trans-6-Aminocyclohept-3-enols, a New Designed Polyfunctionalized Chiral Building Block for the Asymmetric Synthesis of 2-Substituted-4-hydroxypiperidines

trans-6-Aminocyclohept-3-enols 18 and ent-18 are new designed polyfunctionalized chiral building blocks for piperidine alkaloids synthesis and are prepared in high yields from the enzymatically derived cyclohept-3-ene-1,6-diol monoacetate (−)-8. Efficient highly enantioselective syntheses of cis-4-hydroxypipecolic acid (1) and piperidines 3 and 4, in both enantiomeric forms, are described.