Chlorine-containing mixed halogen adducts of triphenylphosphine, triphenylarsine, and triphenylstibine
Abstract
Conductometric titrations of PPh3Cl2 and AsPh3Cl2 with halogens and interhalogens show that the reactions are simple leading to the formation of adducts of types MPh3Cl2X2(M = P or As; X2= Br2, I2, ICl, or IBr) and MPh3Cl5I (M = P or As) in acetonitrile. The high molar conductances of the adducts suggest their formulation as MPh3Cl+ClX2– and MPh3Cl+ICl4– respectively. The polyhalide ions present have been identified from the u.v. spectra of the acetonitrile solutions. The reactions of MR3(M = P, As, or Sb) with ICl and ICl3 also give rise to highly conducting adducts in acetonitrile but the conductometric titration graphs indicate that these reactions are complex. Some of the adducts (PPh3Cl3I, AsPh3Cl3I, and AsPh3Cl5I) have been obtained as crystalline solids.