Efficient Synthesis of Isothiochromene Derivatives by Pd-Catalyzed Hydrothiolation Reaction

An efficient method for the preparation of isothiochromene derivatives through the palladium‐catalyzed intramolecular hydrothiolation reaction of halides and thiourea is reported. Two carbon–sulfur bonds are formed in this one‐pot palladium‐catalyzed cascade reaction. This new protocol is free from foul‐smelling thiols and operates under mild conditions to give isothiochromene derivatives in excellent yields and with excellent 6‐endo‐dig selectivity. Isothiochromene could be efficiently synthesized by palladium‐catalyzed intramolecular hydrothiolation. This protocol is free of foul‐smelling thiols and enjoys excellent yields and excellent 6‐endo‐dig selectivities.