Tert-Butylthiol
tert-Butylthiol, also known as 2-methylpropane-2-thiol, 2-methyl-2-propanethiol, tert-butyl mercaptan (TBM), and t-BuSH, is an organosulfur compound with the formula (CH3)3CSH. This thiol is used as an odorant for natural gas, which is otherwise odorless. It may also have been used as a flavoring agent. Preparation At least one publication has listed tert-butylthiol as a very minor component of cooked potatoes, but because the tert-butyl moiety is very rare in natural products, other sources doubt the existence of natural sources of the compound. It was first prepared in 1890 by Leonard Dobbin by the reaction of zinc sulfide and t-butyl chloride. The compound was later prepared in 1932 by the reaction of the Grignard reagent, t-BuMgCl, with sulfur to give the corresponding thiolate, followed by hydrolysis. This preparation is shown below: t-BuMgCl + S → t-BuSMgCl t-BuSMgCl + H2O → t-BuSH + Mg(OH)Cl It is currently prepared industrially by the reaction of isobutylene with hydrogen sulfide over a clay (silica alumina) catalyst. Reactions tert-Butylthiol can react with metal alkoxides and acyl chlorides to form thiol esters, as shown in the equation: In the reaction above, thallium(I) ethoxide converts to thallium(I) t-butylthiolate. In the presence of diethyl ether, thallium(I) t-butylthiolate reacts with acyl