(586a) Asymmetric Catalysis Using Organic/aqueous Tunable Solvents

Hallett, J. P., Georgia Institute of Technology
Hill, E. M., Georgia Institute of Technology
Broering, J. M., Georgia Institute of Technology
Bommarius, A. S., Georgia Institute of Technology

The development of Organic/Aqueous Tunable Solvents has opened up possibilities for performing catalytic transformations on nonpolar organic substrates using easily recyclable aqueous-phase biological and organometallic catalysts. OATS uses a mixed organic/aqueous solvent system to permit homogeneous chemical transformations, followed by the application of gaseous CO2 to expand the medium and enable catalyst recovery and product isolation. The product yields and asymmetric selectivity were stable over several cycles, indicating only minor reductions in enzymatic activity throughout the process. This preserves the high activity of homogeneous catalysts while taking advantage of simple separation techniques normally applied to heterogeneous or biphasic catalytic systems. This presentation will focus on the development of a chiral biocatalytic transformation process that uses OATS to enhance productivity. The production across numerous catalytic cycles and the underlying phase equilibria of the system will be reported. Comparisons to other OATS processes, both biocatalytic and organometallic, will be included.