Thus, triphosgene is commonly used as an alternative reagent. Triphosgene exists in a stable crystalline form that is safer and easier to transport, store, and handle than COCl2 gas. However, in recent years triphosgene itself has been reported to be highly toxic, and an alternative method is urgently needed. The on-demand synthesis of COCl2 through the UV-light irradiation of chloroform (CHCl3) was recently reported, which is a simple method that incorporates safe and inexpensive CHCl3 as the solvent and COCl2 precursor. This method requires high-energy UV light, which induces the decomposition of COCl2 as the product as well as the versatility of the substrate. However, although reactions with nucleophiles such as alcohols proceed efficiently, they are not suitable for the synthesis of carbamoyl chlorides from light-unstable amines.