Used primarily as a sulfonating agent in organic synthesis, enabling the introduction of sulfonyl groups into various substrates. It serves as a key intermediate in the preparation of sulfonamides, which are important in pharmaceuticals and agrochemicals. Its reactivity allows for the functionalization of aromatic and heteroaromatic compounds, making it valuable in the development of active ingredients in medicinal chemistry. Additionally, it finds use in polymer chemistry as a cross-linking or modifying agent due to the reactivity of the bromomethyl group.