The formation of three-dimensional self-assembled monolayers (3-D SAMs) generated by the adsorption of n-octadecyl disulfide onto colloidal gold and silver nanoparticles is described. The functionalized nanoparticles were characterized by solubility, transmission electron microscopy, ultraviolet−visible spectroscopy, 1H nuclear magnetic resonance spectroscopy, surface-enhanced Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. On gold nanoparticles, this new functionalization method affords crystalline 3-D SAMs that are indistinct from those prepared by the analogous adsorption of n-octadecanethiol. On silver nanoparticles, however, the films derived from n-octadecyl disulfide appear to be somewhat less crystalline than those prepared similarly from n-octadecanethiol. The origin of this difference is briefly explored and discussed.

The synthesis and characterization of the tridentate “heteroscorpionate” mixed functionality ligand, (2-thiophenyl)bis(pyrazolyl)methane, L1, is reported. This ligand was used to synthesize the complexes, [Fe(L1)2][ClO4], [Co(L1)2][BPh4], and [V(L1)2][BPh4]. X-ray crystallographic analysis of the latter two complexes gave the following structural parameters:  [V(L1)2][BPh4]·MeCN· i Pr2O, C58H57N9B1O1S2V1, monoclinic, a = 16.197(2) Å, b = 19.281(2) Å, c = 17.985(2) Å, β = 102.343(9)°, space group P21/c; [Co(L1)2][BPh4]·CH2Cl2, C51H42N8B1Cl2Co1S2, triclinic, a = 12.751(1) Å, b = 12.830(1) Å, c = 14.740(1) Å, α = 98.351(7)°, β = 98.122(6)°, γ = 97.023(8)°, space group P1̄. An example of the use of this new class of “heteroscorpionate” ligands for systematic comparisons of electronic properties of metal complexes with identical topology that vary only in the nature of one of the donor atoms is given.

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