Tris amine dimers

Tellurium nitride was first obtained by the reaction of TeBt4 with liquid ammonia more than 100 years ago. The empirical formula TeN was assigned to this yellow, highly insoluble and explosive substance. However, subsequent analytical data indicated the composition is Tc3N4 which, in contrast to 5.6a and 5.6b, would involve tetravalent tellurium. This conclusion is supported by the recent preparation and structural determination of Te6N8(TeCl4)4 from tellurium tetrachloride and tris(trimethylsilyl)amine (Eq. 5.5). The TceNs molecule (5.12), which is a dimer of Tc3N4, forms a rhombic dodecahedron in which the... 

Goto et al. (2004) measured the reaction kinetics of one-electron oxidation of A -methyl-p-anisidine in AN. In the electrode process, oxidation was performed at the platinum disk-shaped anode, in the chemical process, by means of the tris(p-bromophenyl)amine cation-radical. In both the cases, after one-electron oxidation, dimerization took place leading to the formation of the dye variamine blue. According to the kinetic data, the mechanism of this dye formation is different in the electrode and chemical processes (see Scheme 2.34). Namely, in the electrode oxidation, the cation-radical appears to be surrounded by a huge amount of the initial (nonoxidized) A-methyl-p-anisidine... 

Oxidation of carboxylate ions in homogeneous solution using some one-electron transfer agents gives in varying proportions the Kolbe dimer and the product from hydrogen atom abstraction from the solvent by the intermediate alkyl radical. Persulphate ion [109], hexachloco-osmate(v) [110] and the radical-cation from tris(4-bromophenyl)amine [111] all have been used to promote this reaction. 

Using this method, the dimerization reactions of short lived methyl-diphenylamine and diphenylamine radical cations are successfully investigated61. In this study tris(4-bromophenyl)amine cation radical (TBPA,+) was used as 1 . Oyama et al.,94 used tris(2,4-dibromophenyl)amine (TDBPA) as the reaction initiator (M,+) and spectroscopically detected anthracene derivative cation radicals in acetonitrile using the ESTF method. This approach holds good potential for evaluation of the reactivities of short lived cation radicals. 

Fleischmann et al s 34 report cyclic voltammetry data for the oxidation of a series of aromatic hydrocarbons in a molten salt electrolyte, AlCl3-NaCl-KCl at 150°. Electrooxidation in this medium occurs at unusually low oxidation potentials. Tris-(p-substituted phenyl)amines, with the exception of tri (p-nitrophenyl) amine, yield very stable radical cations by all electrochemical criteria 380>S42 Mono- and bis-p-substituted triphenylamines, however, dimerize with rate constants ranging from 101 to 10s M 1 sec 1 to benzidines 176 (Eq. (237)), which subsequently are oxidized to the radical cations 177, whose ESR-spectra are observed. Dimerization is fastest with the p-N02 andp-CN-derivative, in accordance with HMO calculations, which predict the highest spin sensity in the p-position of these compounds 542 ... 

Several examples of the use of hexamethyldistannoxane as a Me3Sn group transfer agent are reported. Thus the dimetallic carbonyl dimers of Mo, Mn, Fe, Co, and Ni react with Me3SnOSnMe3 [and also with tris(trimethylstannyl)amine, N(SnMe3)3] to form metal-carbonyl derivatives containing tin complexes (equation 118)277. 

As noted above, the first monomeric pyrazol-l-ylborane was isolated as its trimethyl-amine adduct The compound (CH3)3N—BH2[pz-3,5-(Cp3)2] (Hpz = pyrazoie) was obtained as a distillable material on reaction of (CH3)3N—BH3 with 3,5-bis(tri-fluoromethyl)pyrazole = H[pz-3,5-(Cp3)2] = Hpz. Surprisingly, when THP—BH3 (THF = tetrahydrofuran) was employed as reagent, the dimeric species H2B(p-pz )2BH2, a pyrazabole (see Sect. IV.), was obtained without difficulty Apparently, the two-coordinate nitrogen of the pyrazolyl group in THP—BH2[pz-3,5-(Cp3)2] is sufficiently basic to displace THP but this base displacement cannot occur in the corresponding (CH3)3N—BH2[pz-3,5-(Cp3)j]. 

---