147833-81-6

Basic information

• Product Name: W₂Br₄((C₆H₅)2P(CH₃))4
• CAS NO: 147833-81-6
• Molecular Weight: 1488.2
• Mol File: 147833-81-6.mol
• Article Data: 1

Chemical Properties

• CAS DataBase Reference: W₂Br₄((C₆H₅)2P(CH₃))4(CAS DataBase Reference)
• NIST Chemistry Reference: W₂Br₄((C₆H₅)2P(CH₃))4(147833-81-6)
• EPA Substance Registry System: W₂Br₄((C₆H₅)2P(CH₃))4(147833-81-6)

Safety Data

• Hazardous Substances Data: 147833-81-6(Hazardous Substances Data)

Upstream product

• 13470-11-6 tungsten(V) bromide 
• 1486-28-8 diphenyl(methyl)phosphine 

Relevant articles and documents

A new synthetic route to W4W and Mo4W compounds of the type MM′X4(PR3)4, X = Cl or Br. Structural characterization of W4WBr4(μ-dppm)2 and Mo4WBr4(PMe2Ph)4 and 31P{1H} NMR spectra of these and related compounds

A new synthetic route that is more convenient and more general than any previously available has now been developed for quadruply bonded W24+ compounds. This new synthetic route has been used in the preparation of complex 1, W4WBr4(μ-dppm)2, and in addition two known ditungsten compounds, W2Cl4(PMe3)4 (3) and W2Cl4(PMe2Ph)4 (4). The quadruply bonded complexes 1 and Mo4WBr4(PMe2Ph)4 (2) are formed in the reactions between WBr5 and bis(diphenylphosphino)methane and WBr4(PPh3)2 and Mo(η6-C6H5PMe2)(PMe 2Ph)3, respectively. These are the only examples of quadruply bonded complexes that contain either a W4WBr4 or Mo4WBr4 core. The W4W and apparent Mo4W distances for W4WBr4(μ-dppm)2 and Mo4WBr4(PMe2Ph)4 are 2.2632(9) and 2.209(1) A?, respectively. Complex 2 is contaminated by small amounts of the dimolybdenum analog. In addition to the structural data for these complexes, each has been fully characterized using 31P{1H} NMR and UV-vis spectroscopy. Preliminary spectroscopic data have been obtained for W4WBr4(PMe2Ph)4 (5), W4WBr4-(PPh2Me)4 (6), and Mo4WBr4(PPh2Me)4 (7). Complex 1 has methylene protons located at positions that allow the calculation of the diamagnetic anisotropy of the W4W bond from the 1H NMR chemical shift data. The diamagnetic anisotropy for the W4W bond in W4WBr4(μ-dppm)2 has been estimated and will be compared to the diamagnetic anisotropy estimated for W4WCl4(μ-dppm)2 and α-W4WCl4(dppe)2. The crystal structures of 1 and 2 are fully described. Crystallographic data for these compounds are as follows: compound 1, P21 with a = 10.047(1) A?, b = 14.529(2) A?, c = 23.668(3) A?, β = 95.294(1)?, V = 3440(1) A?3, and Z = 2; compound 2, Fdd2 with a = 18.313(4) A?, b = 43.981(7) A?, c = 9.570(2) A?, V = 7709(2) A?3, and Z = 8.