Continuous Flow Chiral Amine Racemization Applied to Continuously Recirculating Dynamic Diastereomeric Crystallizations.

A new, dynamic diastereomeric crystallization method has been developed, in which the mother liquors are continuously separated, racemized over a fixed-bed catalyst, and recirculated to the crystallizer in a resolution-racemization-recycle (R) process. Separating the racemization from crystallization overcomes problems of using catalysts , that suffer conflicting sets of conditions, inhibition, and separation. Continuous racemization has been achieved through the covalent attachment of [IrCp*I] SCRAM catalyst to Wang resin solid support to give a fixed-bed catalyst.