Tributylstannyl methanesulfonate is primarily used as a catalyst or reagent in organic synthesis, particularly in esterification and transesterification reactions. It facilitates the formation of esters from carboxylic acids and alcohols, making it valuable in the production of polymers, plasticizers, and fine chemicals. Additionally, it is employed in the synthesis of complex organic molecules, including pharmaceuticals and agrochemicals, due to its ability to enhance reaction efficiency and selectivity. Its role in promoting carbon-carbon bond formation also makes it useful in advanced organic transformations.