Thallium amide

Metal-Nitrogen Bond Lengths and Torsion Angles between the Metal and Nitrogen Coordination Planes for Three-Coordinate Aluminum, Gallium, Indium, and Thallium Amides... 

The chemistry of alkyl- and arylaluminum, gallium, indium, and thallium amides has been investigated much more than the comparable chemistry of Group II elements (9,13-18). Alkylaluminum amides especially have a very rich and diverse structural chemistry (9,13-15). When a trialkylalane reacts with primary or secondary amines, the amides 3,3, and 4 are formed in addition to a simple adduct [Eqs. (3) and (4)]. 

Interestingly, this does not happen during the synthesis of MeSi[SiMe2N(Tl)t-Bu]3. However, it is possible to obtain the partially demetalated thallium amide [MeSi SiMe2N(H)t-Bu SiMe2N(Tl)t-Bu 2] via the controlled thermolysis of MeSi[SiMe2N(Tl)t-Bu]3. ... 

Although the chemistry of thallium compounds bears some resemblance to that of alkali metal analogs, thallium bis(trimethylsilyl)amide was only structurally characterized <1994JOM167>. Lappert and co-workers have reported on the reactions of the corresponding sodium and thallium amides MN(SiMe3)2 with 1,3,5-triazine, and the structures of the novel products, 1,3,5,7-tetraazaheptatrienylsodium 20 and -thallium 21 (Equation 2). 

Thallium Nitride. TI3N, mw 627.18, N 2.23%, blk needles, mp not reported. Hydrolyzed by steam. Sol in K amide-ammonia soln. Prepd by reacting K amide in liq ammonia with Tl nitrate. T13N explds when shocked and on contact with w or weak acids Ref 1) Gmelin, Syst Nr 38 (1940), 234... 

Like thallium(I) amide from which it is derived by treatment with potassium amide in liquid ammonia, the ammoniated salt (x = 2 or less) explodes violently on heating, friction, or contact with dilute acids or water. 

Dialkyl and diarylthallium(III) derivatives are stable, crystalline solids that melt at 180—300°C. The dimethyl thallium derivatives of CN", C10 4, BF 4, and NO 3 contain linear (CH3)2T1 cations and the free anions (19). In aqueous solutions, they ionize to the (CH3)2T1(H20)+ ions, except those derivatives containing alkoxide, mercaptide, or amide anions, which yield dimeric structures (20,21). 

The first well characterized thallium(I) derivative of a monodentate amide ligand was the silylamide [ TlN(SiMe3)2 2] obtained from LiN(SiMe3)2 and TlCl in toluene. It is a centro-symmetric dimer with an almost perfectly square planar TI2N2 core as shown in Figure 8.12. ... 

Monomeric thallium(I) amides and related species have also be obtained by using chelating amido or related ligands, as in the p-diketiminato complexes [Tl( NDippC-(R) 2CH)] (R = CH3 or (T ) " and TIL (L = N(SiMe3)C(Ph) 2CH or N(Dipp)C-... 

The dimeric thallium(III) amide [( fo (pentafluorophenyl) Tl(dpa))]2 " (where Hdpa = 2,2 -dipyridylamine) comprises distorted trigonal bipyramidal thallium(III) ions that are coordinated by two pentafluorophenyl groups (TI—C distances are 2.12(4) and 2.16... 

The heterocycles react directly with alkali metals or undergo exchange reactions with, for example, sodium amide and hydride, n-butyllithium and thallium ethoxide, to form the TV-heteroaryl salts. The salts of the alkali metals exist as solvent separated ion-pairs or as contact ion-pairs (71JOC3091), as do the quaternary ammonium salts, whereas the salts of the heavier metals are generally considered to have a high N—metal covalent character. These characteristics, which can be modified by a change in the polarity of the solvent, control the reactions of the heteroaryl anions. 

Thallium(III) trifluoroacetate, 295 Trichlorosilane-t-Amines, 322 Tris(tetrabutylammonium) pyrophosphate, 338 Amidation... 

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