Group 15 elements Trimethyl derivatives

Summary Trimethyl- and triisopropyl-silyl diazomethane derivatives have been used for the synthesis of new types of diazo derivatives including those featuring a heavier main-group element or a transition metal directly bound to the diazo-carbon. They are also precursors to a variety of stable nitrilimines and carbodiimides, and stable pseudo-diazoalkenes and carbenes. (Phosphino)(silyl)carbenes have been used in the synthesis of new types of heterocycle including some stable four-7c-electron four-membered derivatives. 

Structure and bonding in the gaseous monochlorides, trichlorides and trimethyl derivatives of the Group 13 elements... 

Table 11.1. Gaseous, monomeric mono- and tri-chlorides of the Group 13 elements M-Cl bond distances, R (in pm), and bond energies, Dq or MBE (in kJ mol ). The Tl-Cl bond distance and the mean bond energy of TICI3 are unknown, presumably because of the low stability of the gaseous trichloride relative to the monochloride. Gaseous monomeric trimethyl derivatives M-C bond distances and mean bond energies. ...

All the Group 13 elements form methyl derivatives of composition M(CH3)3. The trimethyl derivatives of B, Ga, In and T1 are monomeric in the gas phase. Gaseous trimethylaluminum. 

Fig. 11.1. Group variation of bond distances in the subvalent Group 13 element chlorides, MCl(g), in the Lewis-valent trichlorides, MCl3(g) and in the trimethyl derivatives M(CH3)3.

Organo derivatives of group 15 elements Trimethyl phosphite 81 [21] Triphenylarsine 104 [21]... 

Early NMR data were obtained on trimethyl and di-methylphenyl derivatives of the group 15 elements, MeaE and MeaPhE (E = N, P, As, Sb, Bi). The methyl group chemical shift changes in each series were attributed to the electronegativity of the central atom. Subsequently, similar studies were reported by C NMR. Detailed and C NMR data have been reported for two series of tertiary arsines, RaAs and Me AsR. ... 

Table 15.1. Gaseous trihydrogen, trimethyl and trichloro derivatives of the Group 15 elements. E-H, E-C and E-Cl bond distances, R (in pm) mean bond energies, MBE (in kJ mol ) and valence angles ZHEH, ZCEC, and ZCIECI (in degrees).

Many of the applications of group IV element NMR are relatively straightforward from a spectroscopic point of view and are therefore not discussed here. Worthy of special note, however, are Si studies of aqueous silicates and silicones, molten silicates, and silyl transition metal derivatives the use of Si/ H 2D correlation spectra to make assignments and the substantial and growing body of body of Si MAS and/or CP work on solid materials such as zeolites, other silicate minerals, polysilanes, and surface-immobilized materials. The potential of solid-state NMR for Sn and Pb has yet to be fully realised, although solid trimethyl stannyl hydroxide and tributyl stannyl fluoride have been studied. 

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