Recent Progress in the Synthesis of Substituted Benzo[b]furan Derivatives

furan structure is found in many natural products and bioactive compounds. Benzo[b]furan derivatives have attracted the attention of pharmaceutical chemists because of their antiviral, anticancer, insecticidal and anti inflammatory, analgesic and antioxidant activities. At present, many effective synthetic methods have been reported and become one of the hot topics of organic synthesis research in recent years. The research progress in the synthesis of substituted benzo[b]furan derivatives by cyclization or coupling reaction under the conditions of transition metal catalysis and catalysts free in recent ten years is reviewed.