Jacques Gelas

A practical asymmetric synthesis of 2,6-cis-disubstituted piperidines

Abstract A highly diastereoselective intramolecular Mannich reaction involving enantiopure α-methylamine 7 and achiral aldehydes is employed to prepare enantiomerically pure 2,6- cis -disubstituted piperidines. This methodology provides an efficient and selective route to 2,6- cis -disubstituted piperidines, 2,6- cis -disubstituted 4-piperidones and 2,6- cis -disubstituted 4-piperidinols.

A new stereoselective synthesis of chiral optically pure 4-piperidones

Abstract A novel approach to optically pure and functionalized 4-piperidones using diene tricarbonyl iron complexes is described.

Diastereoselective elaboration of 2,3,4-substituted piperidines using diene iron tricarbonyl complexes. Total synthesis of (±)-dienomycin C and (±)-4-epi-dienomycin C

The diastereoselective formation of 2,3,4-substituted piperidines is achieved by condensation of the iron dienal complex 2 and the primary amine 3 via an intramolecular Mannich-type cyclisation. This method is illustrated by the first total synthesis of (±)-dienomycin C 1 and its C-4 epimer 9.

Asymmetric synthesis of C-6 substituted pipecolic acid derivatives

Abstract The synthesis of C-6 substituted pipecolic acid derivatives using an intramolecular Mannich-type reaction is described.

Stereoselective Synthesis of Substituted Piperidines – Total Synthesis and Absolute Configurations of (+)- and (–)-Dienomycin C

The first total asymmetric synthesis and the attribution of the absolute configurations of (+)-dienomycin C (1), an alkaloid isolated from a Streptomyces strain, are reported. This compound was prepared in six steps from the enantiopure tricarbonyl(dienal)iron complex (+)-4 which is easily obtained by separating preformed diastereomers, starting from phenylpentadienoic acid and (S)-methyl mandelate.