The [4+2] annulation of o-acylamino-aryl MBH carbonates with coumarins: facile access to tetrahydrochromeno[4,3-b]quinolin-6-ones†
Abstract
A [4+2] annulation reaction of o-acylamino-aryl MBH carbonates with 3-substituted coumarins has been developed. This method exhibits excellent substrate tolerance and constructs a series of tetrahydrochromeno[4,3-b]quinolin-6-ones with yields up to 95%. The application value of this method has also been demonstrated through a 50-fold scale-up.