Rh-Catalyzed Dehydrogenative Cyclization Leading to Benzosilolothiophene Derivatives via Si–H/C–H Bond Cleavage

Straightforward syntheses leading to π-extended benzosilolothiophene (BST) derivatives by Rh-catalyzed dehydrogenative cyclization reactions have been developed. Electron-deficient ligands were effective for the reactions, and dppe-F20 gave the best result. This method could be applied to the synthesis of highly π-extended ladder-type BST derivatives, which exhibited fluorescence.