Thiophosphoryl bromide

Thiophosphoryl bromide can be prepared by heating phosphorus tribromide with phosphorus pentasulfide, or with elemental sulfur in an inert atmosphere at 130 °C.{{cite book | title = The Chemistry of Phosphorus | series = Permanon Texts in Inorganic Chemistry | volume = 3 | author = Arthur D. F. Toy | year = 1975 | publisher = Permanon Press | isbn = 9781483139593 | page = 438}}

Thiophosphoryl bromide is one product of the bromination of Phosphorus sulfides#P4S7 in cold carbon disulfide:

:{{chem2|3 P4S7 + 12 Br2 → 2 PBr3 + 2 PSBr3 + 2 P2S6Br2 + 2 P2S5Br4}}

Thiophosphoryl bromide has tetrahedral molecular geometry and C_3v molecular symmetry. According to gas electron diffraction, the phosphorus–sulfur bond length is 1.895 Å and the phosphorus–bromine bond length is 2.193 Å, while the {{chem2|S\dP\sBr}} bond angle is 116.2° and the {{chem2|Br\sP\sBr}} bond angle is 101.9°.{{cite journal | title = An electron diffraction determination of the molecular structures of phosphoryl bromide and thiophosphoryl bromide | first1 = E. Jean | last1 = Jacob | first2 = Donald D. | last2 = Danielson | first3 = Svein | last3 = Samdal | journal = J. Mol. Struct. | year = 1980 | volume = 62 | issue = 2 | pages = 143–155 | doi = 10.1016/0022-2860(80)85232-X | bibcode = 1980JMoSt..62..143J}}

Thiophosphoryl bromide is soluble in carbon disulfide, chloroform and diethyl ether.

Like other phosphoryl and thiophosphoryl halides, thiophosphoryl bromide readily hydrolyses, undergoes nucleophilic substitution and forms adducts with Lewis acids.{{cite journal | title = Adducts of thiophosphoryl compounds with metal halides. Part III: Addition compounds of phosphoryl bromide and thiophosphoryl bromide | first1 = W. | last1 = van der Veer | first2 = F. | last2 = Jellinek | journal = Recl. Trav. Chim. Pays-Bas | year = 1970 | volume = 89 | issue = 8 | pages = 833–844 | doi = 10.1002/recl.19700890809}} Reaction with lithium iodide generates the mixed thiophosphoryl halides {{chem2|PSBr2I}} and {{chem2|PSBrI2}} but not thiophosphoryl iodide, {{chem2|PSI3}}.{{cite journal | title = The identification of some new thiophosphoryl compounds containing P–I bonds by means of ³¹P N.M.R. spectroscopy | first1 = K. B. | last1 = Dillon | first2 = M. G. | last2 = Craveirinha Dillon | first3 = T. C. | last3 = Waddington | journal = Inorg. Nucl. Chem. Lett. | volume = 13 | issue = 8 | year = 1977 | pages = 349–353 | doi = 10.1016/0020-1650(77)80109-8}} Thiophosphoryl bromide is of use in organic synthesis for reducing sulfoxides to thioethers,{{cite journal | title = Thiophosphoryl bromide: a new reagent for the reduction of sulfoxides to sulfides | first1 = I. W. J. | last1 = Still | first2 = J. N. | last2 = Reed | first3 = K. | last3 = Turnbull | journal = Tetrahedron Lett. | year = 1979 | volume = 20 | issue = 17 | pages = 1481–1484 | doi = 10.1016/S0040-4039(01)86183-9}} and sulfines to thioketones.{{cite journal | title = Phosphorus Pentasulfide and Thiophosphoryl Bromide: Facile Reagents for the Reduction of Sulfines to Thiones | first1 = J. A. M. | last1 = Kuipers | first2 = B. H. M. | last2 = Lammerink | first3 = I . W. J. | last3 = Still | first4 = B. | last4 = Zwanenburg | journal = Synthesis | year = 1981 | volume = 1981 | issue = 4 | pages = 295–297 | doi = 10.1055/s-1981-29423 | s2cid = 98302665 | url = https://research.utwente.nl/en/publications/phosphorus-pentasulfide-and-thiophosphoryl-bromide-facile-reagents-for-the-reduction-of-sulfines-to-thiones(807b64c5-6275-40f9-8560-c76f81c41a96).html}}

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Category:Thiophosphoryl compounds