Synthesis, Structure, and Reactivity of [RuCl(PP)L]PF(6) (PP = (PPh(3))(2), Ph(2)P(CH(2))(4)PPh(2); L = P(py)(3), PPh(py)(2), py = 2-pyridyl). The "Missing" P,N,N'-Coordination Mode for 2-Pyridylphosphines.
The complexes [RuCl(PPh(3))(2)(P,N,N'-PPh(3-)(x)()(py)(x)())]PF(6) (x = 2, 1b; 3, 1c; py = 2-pyridyl) were isolated from the reaction of RuCl(2)(PPh(3))(3) with 1 equiv of PPh(3-)(x)()(py)(x)() and NH(4)PF(6) in acetone. Crystals of 1b (C(52)H(43)ClF(6)N(2)P(4)Ru) are monoclinic, a = 17.795(2), b = 11.375(4), and c = 23.343(2) Å, beta = 97.012(8) degrees, Z = 4, space group P2(1)/c; those for 1c (C(51)H(42)ClF(6)N(3)P(4)Ru) are monoclinic, a = 17.812(1), b = 11.353(2), and c = 23.391(1) Å, beta = 97.738(5) degrees, Z = 4, space group P2(1)/c. The isomorphous structures were solved by the Patterson method and were refined by full-matrix least-squares procedures to R = 0.036 and 0.033 (R(w) = 0.035 and 0.031) for 7690 and 8121 reflections with I >/= 3sigma(I), respectively. The P,N,N'-coordination mode for 2-pyridylphosphines is previously unreported. The P,N-coordinated complexes cis-RuCl(2)(dppb)(PPh(3-)(x)()(py)(x)()) (x = 1-3; dppb = Ph(2)P(CH(2))(4)PPh(2)) were made by isomerization of the corresponding trans-dichloro isomers, which are themselves synthesized from RuCl(2)(dppb)(PPh(3)). The cis complexes in CHCl(3) or CH(2)Cl(2) dissociate chloride reversibly with formation of P,N,N'-coordinated PPh(3-)(x)()(py)(x)() species, which were isolated as [RuCl(dppb)(PPh(3-)(x)()(py)(x)())]PF(6) (x = 2, 3). Reactions of CO with the species containing the strained P,N,N'-coordination mode lead to displacement of a coordinated pyridyl and formation of the P,N-coordinated complexes [RuCl(CO)(PP)(PPh(3-)(x)()(py)(x)())]PF(6) (PP = (PPh(3))(2), x = 2, 3; and PP = dppb, x = 2, 3). The CO reactions are partially reversible. Solution structures of the complexes were determined by NMR, IR, and UV-visible spectroscopies and conductivity.
Schutte
Richard P.
RP
Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1.
Rettig
Steven J.
SJ
Joshi
Ajey M.
AM
James
Brian R.
BR