Pentafluorophenyl isocyanate (PFPI), an aryl isocyanate, is an N-protecting reagent. The photoinduced intermolecular carbamoylation of tertiary ethereal C-H bond of fused bicyclic system using PFPI/benzophenone has been reported. Reacting wood polymers with PFPI can make them resistant to fungal attack by forming a stable carbamate bond.