Used primarily as a reagent in organic synthesis, particularly in peptide and protein chemistry. It serves as a protecting group modifier, helping to block specific functional groups during complex molecule assembly. Commonly applied in the preparation of active esters and carbamates, it facilitates controlled reactions in pharmaceutical manufacturing and biochemical research. Its reactivity allows for efficient carbonylation under mild conditions, making it valuable in the development of agrochemicals, specialty polymers, and fine chemicals. Requires careful handling due to its moisture sensitivity and potential to release phosgene upon decomposition.