Autocatalytic Mannich Reaction

Significance

The authors report an autocatalytic Mannich reaction in aqueous solvent systems. The two-component indirect Mannich reaction of cyclohexanone with imine 1 leading to product 2 was catalyzed by 10-20 mol% of enantiopure syn-product 2. The best results were achieved in pH 7 buffered water, where general base catalysis was circumvented. In this case the dr was 69:31 (syn) with an er of 96:4. In addition the three-component Mannich reaction was performed, how­ever with inferior results.