Jump to main content
Jump to site search

Issue 22, 2010
Previous Article Next Article

Towards multistranded molecular wires: Syntheses, structures, and reactivities of tetraplatinum bis(polyynediyl) complexes with [upper bond 1 start]Pt-Cx-Pt-(P(CH2)3P)2-Pt-Cx-Pt-(P(CH2)3P[upper bond 1 end])2 cores (x = 4, 6, 8)

Author affiliations

Abstract

Reactions of trans,trans-(C6F5)(p-tol3P)2Pt(C[triple bond, length as m-dash]C)nPt(Pp-tol3)2(C6F5) (PtCxPt; x = 2n) and the 1,3-diphosphine Ph2P(CH2)3PPh2 (2.5 equiv) give the tetraplatinum complexes trans, trans,trans,trans-(C6F5)[upper bond 1 start]Pt(C[triple bond, length as m-dash]C)nPt(C6F5)(PPh2(CH2)3Ph2P)2(C6F5)Pt(C[triple bond, length as m-dash]C)nPt(C6F5)(PPh2(CH2)3Ph2P[upper bond 1 end])2 ([Pt′CxPt′]2; x = 4/6/8, 39%/95%/81%). Crystal structures of [Pt′C8Pt′]2 and two solvates of [Pt′C6Pt′]2 are determined. These confirm that each diphosphine spans two platinum atoms from different Pt(C[triple bond, length as m-dash]C)nPt linkages, as opposed to (1) the 1,2-diphosphine Ph2P(CH2)2PPh2, which under similar conditions with PtC8Pt affords the diplatinum bis(chelate) cis,cis-([upper bond 1 start]PPh2(CH2)2Ph2P)(C6F5)Pt[upper bond 1 end](C[triple bond, length as m-dash]C)4[upper bond 1 start]Pt(C6F5)(PPh2(CH2)2Ph2P[upper bond 1 end]) (73%) or (2) α,ω-diphosphines with longer methylene chains, which span the platinum termini. The formulation [Pt′C4Pt′]2 is supported by a reaction with PEt3 (10 equiv) to give trans,trans-(C6F5)(Et3P)2Pt(C[triple bond, length as m-dash]C)2Pt(PEt3)2(C6F5). In [Pt′C8Pt′]2 and one solvate of [Pt′C6Pt′]2, the chains cross at 77.2°–87.7° angles, with the closest interchain carboncarbon distances (3.27–3.61 Å) less than the sum of the van-der-Waals radii. In the other solvate of [Pt′C6Pt′]2, the chains are essentially parallel, and the separation is much greater (4.96 Å). UV-visible spectra show no special electronic interactions. However, cyclic voltammograms indicate irreversible oxidations, in contrast to the partially reversible oxidations of PtC6Pt and PtC8Pt. The initially formed radical cations are proposed to undergo rapid chain–chain coupling. The new complexes decompose without melting above 185 °C. With [Pt′C8Pt′]2, IR spectra indicate the formation of a new C[triple bond, length as m-dash]C-rich substance.

Graphical abstract: Towards multistranded molecular wires: Syntheses, structures, and reactivities of tetraplatinum bis(polyynediyl) complexes with  [[upper bond 1 start]] Pt-Cx-Pt-(P(CH2)3P)2-Pt-Cx-Pt-(P(CH2)3P [[upper bond 1 end]] )2 cores (x = 4, 6, 8)

Back to tab navigation

Supplementary files

Publication details

The article was received on 01 Feb 2010, accepted on 01 Apr 2010 and first published on 07 May 2010


Article type: Paper
DOI: 10.1039/C002041A
Dalton Trans., 2010,39, 5260-5271

  •   Request permissions

    Towards multistranded molecular wires: Syntheses, structures, and reactivities of tetraplatinum bis(polyynediyl) complexes with [upper bond 1 start]Pt-Cx-Pt-(P(CH2)3P)2-Pt-Cx-Pt-(P(CH2)3P[upper bond 1 end])2 cores (x = 4, 6, 8)

    G. R. Owen, S. Gauthier, N. Weisbach, F. Hampel, N. Bhuvanesh and J. A. Gladysz, Dalton Trans., 2010, 39, 5260
    DOI: 10.1039/C002041A

Search articles by author

Spotlight

Advertisements