The structural and reaction chemistries of some platinum metal complexes
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
The work described in this thesis is concerned principally with the preparation, photochemistry, and structural chemistry of some platinum metal complexes. The work is in two parts. The first part is a study of the photochemistry of complexes of the stoichiometric type M(NO)XnL₂ n = 2 or 3 for M = Ru, Rh, Os, Ir; X = Cl, Br, I; and L = R₂s, R₂se, Ph₃P, Ph₃As, and Ph₃ Sb, and the second part is on the preparative and structural chemistries of halogeno- complexes of iridium, ruthenium and rhodium. The main photochemical reaction observed was oxidation of the ligand (R₂S and R₂Se to R₂SO and R₂Seo, and R₃E to R₃E to R₃EO for E = P, As, Sb), and in many instances the oxidised ligand subsequently coordinated to the complex. The oxidation is achieved with nitrogen oxides (NO, NO₂) for the organosulphides, organoselenides, triphenylphosphine and triphenylarsine, whereas for the triphenylstibine, O₂ appears to be the oxidisng agent. The photochemical reactions of the nitrosyl complexes were investigated using ¹H n.m.r., infrared, UV-visible and mass spectrometric methods. The X-ray single crystal structures were determined on some starting materials and on some crystalline materials isolated during preparations of the complexes investigated in this work. The structures determined were; RhCl₃(Et₂s)₂(Et₂SO), space group P1, a = 9372(4) Å, b = 9.608(5) Å, c = 12.449(6) Å, α = 79.52(4)°, β = 86.88(3), Υ = 70.66(3)°; Os(NO)Br₃(Et₂S)(Et₂SO) space group P2₁/c, a = 13.398(3) Å, b= 8.501(2) Å, c = 16.199(3) Å, β = 105.69(1)°; Ru(NO)Br₃(Et₂PPh)₂ space group P2₁/c, a = 13.505(2) Å, b = 7.389(0) Å, c = 24.492(3) Å, β = 91.22(1), and Os(NO)Cl₂(Et₂PPh)₂(CH₃OCH₂CH₂O) space group P2₁/c; a= 10.869(1) Å, b = 11.381(1) Å, c= 22.673(2) Å β = 102.17(1)°. During the preparative study of some trihalogenostannato complexes of the type A₃[MCln(SnX₃)6-n] M = Rh, Ir; n = 1-3, a number of halogeno- complexes were produced. The X-ray single crystal structures of K₃[IrCl₆] space group P2₁/c; a₁= 12.500(7) Å, b=7.424(6) Å, c = 11.831(10) Å, β= 108.48(6)°, (H₃O)₂[IrBr₆] space group Fm3m; a = 10.2738(28) Å, (NH₄)₂[IrBr₆] space group Fm3m, a = 10.440(2) Å, A₃ [Ircl₅(SnCl₃)] for A = K space group Pmn2₁, a=9.5873(13) Å, b = 9.5170(15) Å, c = 7.8480(9)Å, and A= NH₄ space group Pmn2₁, a= 9.593(3) Å, b = 9.495(2) Å, c = 7.832(2) Å, were determined. A review of the preparative and X-ray structural studies of the platinum metal halogeno- complexes Ru, Os, Rh, Ir, has been prepared, covering the period from 1967 to 1987.