bis(trifluoromethyl) disulfide bis(trifluoromethyl) disulfide bis(trifluoromethyl) disulfide (tfd) is a fluorinated organosulfur compound that was used as a fumigant. it is also an intermediate in the synthesis of triflic acid. it is a volatile liquid that is extremely toxic by inhalation. bis(trifluoromethyl) disulfide names other names hexafluorodimethyl disulfidetfd identifiers cas number 372-64-5 y 3d model (jsmol) interactive image chemspider 61112 pubchem cid 67795 comptox dashboard (epa) dtxsid4073172 inchi inchi=1s/c2f6s2/c3-1(4,5)9-10-2(6,7)8key: cgmffoxaqvruaz-uhfffaoysa-n smiles c(f)(f)(f)ssc(f)(f)f properties chemical formula c2f6s2 molar mass 202.13 g·mol−1 appearance liquid boiling point 35 °c (95 °f; 308 k) except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). infobox references synthesis tfd can be produced by reaction of perchloromethyl mercaptan or thiophosgene with sodium fluoride. toxicity tfd is extremely toxic by inhalation. tfd is a powerful pulmonary agent that can cause severe pulmonary edema. tfd is about half as toxic as perfluoroisobutene.