Product Switch Amine separation and catalyst recycling

Scientists at the RWTH Aachen University invented a straightforward method for the separation of amines produced via homogeneous catalyzed processes allowing the reutilization of the catalyst. Product Switch is particularly attractive for industrially relevant Buchwald-Hartwig (B-H) coupling reactions (enantioselective) catalytic hydrogenation of imines and enamines reduction of amides nitriles and nitro- compounds as well as for hydroamination and hydroamino¬methylation reactions. This new integrated protocol enables a gentle catalyst separation and product isolation using standard glass equipment generates no salt load and preserves catalyst's integrity. The formation of CO2–amine adducts is the key idea behind Product Switch allowing the facile separation of amines from organic solutions under very mild conditions. The catalyst remains active in the organic phase and can be reused. Product Switch allows the separation and the isolation of all single components even in the complex case of the Buchwald-Hartwig reaction containing catalyst products (amines) and by-products (adducts of organic base and inorganic acid or inorganic salts).