Synthesis of cis-5-Trifluoromethylproline from l-Glutamic Acid

Abstract

The diastereoselective synthesis of cis-5-trifluoromethylproline (5-Tfm-Pro) from l-glutamic acid is described. 5-Tfm-Pro could be obtained through a seven-step linear sequence. Trifluoromethylation of the glutamic-derived ester or aldehyde and subsequent reduction of the cyclic imine are the key steps in the synthesis.

Key words

amino acids - cis-5-trifluoromethylproline - fluorine - ­diastereoselective synthesis - imine - reduction

• References and Notes

• 1 Present address: Calyx Chemicals & Pharmaceuticals Ltd, A-37/38, MIDC, Dombivli East, Dist. Thane 421 203, Maharashtra, India.
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