Martin's sulfurane is the organosulfur compound with the formula Ph<sub>2</sub>S[OC(CF<sub>3</sub>)<sub>2</sub>Ph]<sub>2</sub> (Ph = C<sub>6</sub>H<sub>5</sub>). It is a white solid that easily undergoes sublimation. The compound is an example of a hypervalent sulfur compound called a sulfurane. As such, the sulfur adopts a see-saw structure, with a lone pair of electrons as the equatorial fifth coordinate of a trigonal bipyramid, like that of sulfur tetrafluoride (SF<sub>4</sub>). The compound is a reagent in organic synthesis. One application is for the dehydration of a secondary alcohol to give an alkene: