Diastereoselective Approach to cis-4-Methyl/thiol-Pipecolic Esters Based on RCM Reaction and Conjugate Michael Addition

Abstract

A synthetic route for the access to enantiopure cis-4-methyl/thiol-pipecolic esters is presented. It is based on the ring-closing metathesis reaction to build the α,β-unsaturated piperidin-2-one derived from (S)-(–)-phenylethylamine, followed by either diastereoselective conjugate addition of methylorganocuprate allowing access to cis-4-methyl pipecolic ester or by tandem diastereoselective hydrosulforization–thionization reaction providing access to cis-4-thiol pipecolic ethyl esters.

GRAPHICAL ABSTRACT

Keywords:

• Diastereoselective Michael addition
• hydrosulforization
• pipecolic esters
• ring-closing metathesis

Notes

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