A one-pot [Bmim]OH-mediated synthesis of 3-benzamidocoumarins

The first example of an ionic liquid-promoted one-pot synthesis of 3-benzamidocoumarins from salicylaldehydes and 2-pheny-1,3-oxazolan-5-one via Knoevenagel condensation-ring transformation cascades has been reported. No by-product formation, operational simplicity, ambient temperature and high yield (85-97%) are the salient features of the present synthetic protocol. After isolation of the product, the ionic liquid, [Bmim]OH can be easily recycled for further use without any loss of efficiency.