Supported by the National Basic Research Program of China(No.2013CB531800), the National Natural Science Foundation of China(Nos.81402822, 81302793) and the Science and Technology Project of Liaoning Province of China(No.2014204007).
An expedient and efficient method for selective methylation of catechol coumarins by working with different alkalis under appropriate reaction conditions was reported. Esculetins were selectively methylated at positio...