15616-85-0Relevant articles and documents
Reversible capture of small molecules on bimetallaborane clusters: Synthesis, structural characterization, and photophysical aspects
Bould, Jonathan,Base, Tomas,Londesborough, Michael G. S.,Oro, Luis A.,MacIas, Ramon,Kennedy, John D.,Kubat, Pavel,Fuciman, Marcel,Polivka, Tomas,Lang, Kamil
, p. 7511 - 7523 (2011/10/03)
Metallaborane compounds containing two adjacent metal atoms, [(PMe 2Ph)4MM′B10H10] (where MM′ = Pt2, 1; PtPd, 7; Pd2, 8), have been synthesized, and their propensity to sequester O2, CO, and SO 2 and to then release them under pulsed and continuous irradiation are described. Only [(PMe2Ph)4Pt2B 10H10], 1, undergoes reversible binding of O2 to form [(PMe2Ph)4(O2)Pt2B 10H10] 3, but solutions of 1, 7, and 8 all quantitatively take up CO across their metal-metal vectors to form [(PMe2Ph) 4(CO)Pt2B10H10] 4, [(PMe 2Ph)4(CO)PtPdB10H10] 10, and [(PMe2Ph)4(CO)Pd2B10H10] 11, respectively. Crystallographically determined interatomic M-M distances and infrared CO stretching frequencies show that the CO molecule is bound progressively more weakly in the sequence {PtPt} > {PtPd} > {PdPd}. Similarly, SO2 forms [(PMe2Ph)4(SO 2)Pt2B10H10] 5, [(PMe 2Ph)4(SO2)PtPdB10H10] 12, and [(PMe2Ph)4(SO2)Pd2B 10H10] 13 with progressively weaker binding of the SO 2 molecule. The uptake and release of gas molecules are accompanied by changes in their absorption spectra. Nanosecond transient absorption spectroscopy clearly shows that the O2 and CO molecules are liberated from the bimetallic binding site with high quantum yields of about 0.6. For 3, in addition to dioxygen release in the triplet ground state, singlet oxygen O2(1Δg) was also detected with a quantum yield 2 and CO molecules, from 3 and 4 respectively, is an ultrafast process taking place on a time scale of tens of picoseconds. For SO2, the release is even faster (2 and Pd 2 adducts, 5 and 13, the release of SO2 is significantly slower (>1 ns). All these compounds may have potential to serve as light-triggered local and instantaneous sources of the studied gases.
Synthesis of heterobimetallic bis(diphenylphosphino)acetylene-bridged palladium-platinum complexes. Crystal and molecular structure of [PdPtCl4(Ph2PC≡CPPh2) 2]·2CHCl3
Clark, Howard C.,Ferguson, George,Kapoor, Pramesh N.,Parvez, Masood
, p. 3924 - 3928 (2008/10/08)
Reaction of [(PMe2Ph)PdCl(μ-Cl)2PtCl(PMe2Ph)] (I) with 1,2-bis(diphenylphosphino)acetylene yields the heterobimetallic complex [Cl2Pd(Ph2PC≡CPPh2)2PtCl 2] (II). Solution studies using 31P and 195Pt NMR spectra reveal that II exists in an equilibrium of the type 2[Cl2Pd(Ph2PC≡CPPh2)2PtCl 2] ? [Cl2Pd(Ph2PC≡CPPh2)2PdCl 2] + [Cl2Pt(Ph2PC≡CPPh2)2PtCl 2]. Crystals of II [as the bis(chloroform) solvate] are monoclinic, space group P21/n with two formula units in a cell of dimensions a = 14.415 (3) A?, b = 12.149 (3) A?, c = 15.949 (3) A?, and β= 91.33 (2)°. The bimetallic complex lies about a crystallographic inversion center, and the Pd and Pt atoms are mutually disordered. The structure was solved by the heavy-atom method and refined by full-matrix least-squares calculations with anisotropic thermal parameters; R = 0.033 and Rw = (ΣwΔ2/ΣwF02)1/2 = 0.044 for 2407 observed reflections. The unique metal atom has slightly distorted square-planar geometry with mean M-Cl = 2.344 (2) A and mean M-P = 2.244 (2) A?. The strained 10-membered PtPdP4C4 ring system is nonplanar; there is significant bowing of the P-C≡C-P moiety [mean P-C ≡C = 172.2 (3)°] and enlargement of the M-P-C(acetylene) angles from tetrahedral [mean value 121.3 (2)°].