Amido compound

Niecke et al. have prepare polyimido analogues of the metaphosphate ion, PO3, bylithiation ofthe corresponding amido compounds [16]. Thus the monomeric solvent-separated ion pair [(THF)4Li][P(NMes )3] (10) is obtained by treatment of (Mes N)2P(NHMes ) with "BuLi [16]. A monomeric contact ion pair (11) containing the unsymmetrical anion [P(N Bu)2(NMes )]" has also been reported [16]. By contrast the dilithium derivative of the trisimidometaphosphate [P(N Bu)3]" forms a dimer (12) [17], with a cubic structure reminiscent of that of (7). 

A first terminal imido complex of nickel (121) was prepared according to Equation (3).468 The synthesis goes via the Ni11 amido compound (122) and uses the steric bulk of the arylimido group for stabilization. The Ni11 center in (121) is planar and three-coordinate. Reaction of (121) with CO or benzyl isocyanide leads to formal nitrene transfer with formation of (124) and (125), respectively. Further reaction with CO liberates the isocyanate and carbodiimide (Equation (4)). 69... 

The preparation of similar precursors suitable for the deposition of metal nitrides is analogous to the preparations of phosphorus and arsenic compounds. The initial reaction of metal trialkyls MR3 (M = A1, Ga, In) with amines (NHR 2) results in the formation of oligomeric amido compounds [R2MNR 2] (n = 2 or 3) which eliminate alkanes on thermolysis. The incorporation of a proton as a substituent on the pnictide bridging ligand has been examined, and many compounds of the type [R2MNHR ]2 have been synthesized. The presence of this proton may facilitate /3-elimination, allowing lower deposition temperatures to be used. 

In the early 1990s supported metallocenes were introduced to enable gas phase polymerisation. Also ethene/a-olefin copolymers with high comonomer content, cycloolefin copolymers and ethene-styrene interpolymers became available. In 1990 Stevens at Dow [22] discovered that titanium cy-clopentadienyl amido compounds (constrained geometry catalysts) are very beneficial for the copolymerisation of ethene and long-chain a-olefins. 

The dependence of the E-E bond lengths on the nature of the substituents has been explained merely by steric effects. However, it seems more likely that a balanced interaction of steric effects, charge separation, electrostatic repulsion, rehybridization etc., causes the observed variation. In contrast to the amido compounds discussed above, a specific correlation between the E-E bond lengths and the bond angles (C-E-C or Si-E-Si) does not exist. The different influence of alkyl and silyl substituents was investigated by quantum-chemical calculations.91... 

This M-peroxo-M-amido complex can also be prepared by the reduction of the M-superoxo-M-amido compound (Sec. E) in aqueous ammonia. The latter method is useful in the prepara-... 

Amido compounds are gaining increasing importance in early transition metal chemistry as supporting ligands, and structures with both phosphorus and nitrogen donor atoms are... 

These compounds, in which trivalent nitrogen bridges phosphoryl radicals, are obtained by heating amido-compounds, with loss of ammonia. The polymerised [NPO] , phosphonitril, has been referred to already (p. 199). 

These metal compounds can be made by high temperature (>100°C) reactions such as that of NH3 with the metal or metal oxide, or by lower temperature routes where metal halides are heated with Li3N or Na3Nn the latter method has been used for Ti, Cr, Mn, Hf, Y, and Sm nitrides. Thin films of nitrides can be made by chemical vapor deposition12 using amido compounds such as Ti(NMe2)4 and NH3 at 150-450°C at 1 atm. 

Ato complexes include [MnMe4]2-75 and the planar mesityl [Mn mes3]-.76 An amido compound with a CH3 bridge is Mn(/j,-Me)[N(SiMe3)2AlMe3]2 2.77... 

A mixed siloxo/amido compound, Y[OSiBu Ar2][N(Me3Si)2]2, has also been characterized.12... 

Also, treatment of the 3-aminoadenosine derivative 530 with EDC HCO3, effects cycliza-tion to form the 3-amido compound 531. ... 

Homoleptic amido compounds of U, U(NR2)5, have been synthesized by oxidation of anionic tetravalent complexes, [U(NR2)5]. A unique hexakisamido U complex has been isolated using 2,3 5,6-dibenzo-7-azabicyclo[2.2.1]hepta-2,5-diene. The [U(dbabh)] anion can be oxidized to form a species both of which have a near-perfect octahedral geometry with the six antido ligands. ... 

The tetrakis(dialkylphosphido) complexes, An(PPP)4 (An = Th, U) PPP = P(CH2CH2P(CH3)2), were prepared by reacting AnC with four equivalents of the lithium or potassium salt of the PPP tetra-anion. The stmcture of these compounds shows triangulated dodecahedra distorted toward bicapped trigonal prisms. These complexes represent one of the first actinide systems containing exclusively metal-phosphorus bonds. These complexes are known to undergo insertion reactions as seen in actinide amido compounds. ... 

Other examples are dinuclear imido amido compounds Sb2(NR2)2(/u-NR)2 and a range of species based on... 

Base-free tris(primary amido) compounds of the type M[N(H)Mes ]3 (M = Al, Ga, In Mes = 2,4,6-Xh-tert-butylphenyl) have been synthesized via the salt elimination reaction of Mes N(H)Li with the respective MCI3. Whereas the singly base-stabilized trw(primary amido) derivatives, [M N(H)Dipp 3(py)j (Dipp = 2,6-diisopropylphenyl), have been prepared via an amine elimination reaction of H2NDipp with [E(NMc2)3]2 These derivatives were also to be examined for their potential as III-V precursors. ... 

Reactions of [Ti( -C5Me4SiMeXCl)Cl3] with two equiv. of LiNH-r-Bu afforded the ania-silyl-jj-amido compounds (j7 j7 -C5Me4SiMeX-N-r-Bu)TiCl2 (X = H,C1). Methylation of (j7 j7 -C5Me4SiMeX-N-r-Bu)TiCl2 with MgClMe gives... 

Actinide(IV) alkoxide complexes have been reported which are coordinated by a variety of other bulky ligand sets. Uranium(IV) amido compounds are reagents for the preparation of homoleptic uranium(IV) alkoxides as well as mixed alkoxide/amido species. A variety of mixed aryloxide-diethylamide derivatives have been pr ared including (U(NEt2)(0-2,6-Bu 2C6H3)3 and U(NEtp(0-2,6-R7CftH3)3. R = Pr . Bu ). The previously described metallacycle... 

Substituted azo-compounds are generally prepared by the action of diazo-compounds on phenols and amines. With the latter bodies the intermediate formation of diazo-amido compounds is often observed. 

After diazotisation is completed the liquid is allowed to run into an alkaline solution of the phenol or its sulphonic acid, care being taken that the mixture remains alkaline. After some time the dyestuff is salted out, and is generally filtered through a filter-press. The combination of diazo-compounds with amines is somewhat more complicated. Some of these, for instance metaphenylenediamine, combine with diazo-compounds in neutral aqueous solutions while others, like diphenylamine, are dissolved in alcohol, and a concentrated solution of the diazo-compound gradually added. In the manufacture of amidoazobenzene and all compounds in which an intermediate formation of a diazo-amido-compound takes place, a large excess of the amine has to be employed, to hold the diazoamido-compound formed in solution. 

The nitroazo-compounds obtained by combination of nitrodiazo-compounds with primary amines may be diazotised and combined with phenols resulting nitrodisazo-compounds on reduction yield amido-compounds, which, when again diazotised and combined with a phenol, yield tertiary azo-compounds, containing three azo-groups. 

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