Structural classification of metal complexes with three-coordinate centres.

Attempts to describe the geometry about three-coordinate silver(i) complexes have proven difficult because interatomic angles generally vary wildly and there is no adequate or readily available classification system found in the literature. A search of the Cambridge Structural Database shows that complexes formed between any metal centre and three non-metal donors (18 001 examples) usually adopt geometries that are quite different than ideal 'textbook' extremes of either trigonal planar (~4% with α = β = γ = 120 ± 2°), T-shaped (~0.05% with α = 180 ± 2°, β = γ = 90 ± 2°), or trigonal pyramidal (~0.

Isomer dependence in the assembly and lability of silver(I) trifluoromethanesulfonate complexes of the heteroditopic ligands, 2-, 3-, and 4-[di(1H-pyrazolyl)methyl]phenyl(di-p-tolyl)phosphine.

Three isomers of a new heteroditopic ligand that contains a di(1H-pyrazolyl)methyl (-CHpz2) moiety connected to a di(p-tolyl)phosphine group via a para-, meta-, or ortho-phenylene spacer (pL, mL, and oL, respectively) have been synthesized by using a palladium(0)-catalyzed coupling reaction between HP(p-tolyl)2 and the appropriate isomer of (IC6H4)CHpz2. The 1:1 complexes of silver(I) trifluoromethanesulfonate, Ag(OTf), were prepared to examine the nature of ligand coordination and the type of supramolecular isomer (monomeric, cyclic oligomeric, or polymeric) that would be obtained. The single crystal X-ray diffraction studies showed that [Ag(pL)](OTf), 1, and [Ag(mL)](OTf), 2, possessed cyclic dimeric dications, whereas [Ag(oL)](OTf), 3, was a coordination polymer.

Homoleptic nickel(II) complexes of redox-tunable pincer-type ligands.

Different synthetic methods have been developed to prepare eight new redox-active pincer-type ligands, H(X,Y), that have pyrazol-1-yl flanking donors attached to an ortho-position of each ring of a diarylamine anchor and that have different groups, X and Y, at the para-aryl positions. Together with four previously known H(X,Y) ligands, a series of 12 Ni(X,Y)2 complexes were prepared in high yields by a simple one-pot reaction. Six of the 12 derivatives were characterized by single-crystal X-ray diffraction, which showed tetragonally distorted hexacoordinate nickel(II) centers.

Comment on "synthesis, characterization, and structures of persistent aniline radical cation": it is a protonated aniline and not an aniline radical cation.

The same, but different: The reaction of tri-tert-butylaniline (TBA) with AgSbF6 in CH2 Cl2 produces a green-colored intermediate which undergoes decomposition to form a protonated aniline (TBAH(+) SbF6 (-) ). Crystals of the protonated aniline salt were analyzed by X-ray diffraction and found to have the same crystal characteristics as the crystals of the supposed cation radical first identified in 2012.

Electronic communication across diamagnetic metal bridges: a homoleptic gallium(III) complex of a redox-active diarylamido-based ligand and its oxidized derivatives.

Complexes with cations of the type [Ga(L)(2)](n+) where L = bis(4-methyl-2-(1H-pyrazol-1-yl)phenyl)amido and n = 1, 2, 3 have been prepared and structurally characterized. The electronic properties of each were probed by electrochemical and spectroscopic means and were interpreted with the aid of density functional theory (DFT) calculations. The dication, best described as [Ga(L(-))(L(0))](2+), is a Robin-Day class II mixed-valence species.

Syntheses and electronic properties of rhodium(III) complexes bearing a redox-active ligand.

A series of rhodium(III) complexes of the redox-active ligand, H(L = bis(4-methyl-2-(1H-pyrazol-1-yl)phenyl)amido), was prepared, and the electronic properties were studied. Thus, heating an ethanol solution of commercial RhCl(3)·3H(2)O with H(L) results in the precipitation of insoluble [H(L)]RhCl(3), 1. The reaction of a methanol suspension of [H(L)]RhCl(3) with NEt(4)OH causes ligand deprotonation and affords nearly quantitative yields of the soluble, deep-green, title compound (NEt(4))[(L)RhCl(3)]·H(2)O, 2·H(2)O.