We report herein a new, practical, and economic synthesis of the phosphodiesterase inhibitor Rolipram on a multigram scale as well as the synthesis of new 4-aryl pyrrolidones and beta-aryl-gamma-amino butyric acids (GABA derivatives) employing an efficient Heck-Matsuda arylation of 3-pyrroline with aryldiazonium tetrafluoroborates. Racemic Rolipram was resolved into its enantiomers using chiral simulated moving bed chromatography having the low-cost microcrystalline cellulose triacetate as a chiral stationary phase.

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Bupivacaine is an amide type local anesthetic widely used in surgery and obstetrics because of its sustained peripheral and central nerve blockade. R-(+)-bupivacaine is more toxic to the central nervous and the cardiovascular systems than S-(−)-bupivacaine. To obtain S-(−)-bupivacaine with high degree of purity using a continuous simulated moving bed (SMB) unity, equilibrium and mass transfer parameters under dilute conditions were obtained by pulse experiments using 0,0 -bis[4-terc-butyl-benzoyl]-N,N -diallyl-L-tartar diamide immobilized in silica (Kromasil R CHI-TBB). The linear equilibrium constants were found to be 2.12 and 2.91 for R-(+)and S-(−)-bupivacaine, respectively. Axial dispersion coefficients were found to be practically the same for both enantiomers. A fast kinetic of mass transfer was observed. The internal resistance to the mass transfer controls all the mass transfer process in this chiral column and the pore diffusion coefficients were of the order 10 −7 cm 2 /s. The equilibrium and mass transfer parameters will be employed in future simulation and design of operating conditions of SMB unity.

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