L-proline-Brønsted acid deep eutectic mixture (DEM) triggered consecutive Claisen–Schmidt and Michael addition reactions
摘要
We develop a new l-proline-Brønsted acid deep eutectic mixture (DEM)-driven straightforward protocol for the synthesis of (aryl/heteroarylmethylene)bis(3-hydroxy-5,5-dimethylcyclo-hexenone) derivatives with broad functional group compatibility using one-pot consecutive Claisen–Schmidt and Michael addition reactions. These derivatives are obtained under very mild reaction conditions with good yields (65–92%) in a short span (20–30 min). Significantly, a newly developed l-proline-Brønsted acid catalyst system was characterized using D2O exchange proton NMR spectroscopy.
Graphical abstract