Trimethyltin , structure

The resulting derivatives, unlike most organotin carboxylates, are hydrolyzed relatively readily in air. An X-ray crystallographic study 399) showed that trimethyltin glycinate has an intermolecularly associated, polymeric structure, with bridging amino groups. 

Zuckerman et al. have extensively utilized this method in heterocyclic tin(II) chemistry 100). In some cases, this synthesis may also be performed with tin(II) chloride, the starting hydrochloride being coordinated by the addition of an amine 120). Free 171) and metal-bound tin(II) chloride 172) have been treated analogously with trimethyltin hydroxide to yield amorphous powders of the composition Sn(OH)2 and (CO)5MSn(OH)2 (M = Cr, W) and ClSnMe3. Unfortunately, no direct information on the structure of these compounds is available. 

The voh stretching frequency of trimesityltin hydroxide (Ar43SnOH) shows a sharp band at 3629 cm-1, pointing to a monomeric non-associated structure. This is in contrast with the broad band of trimethyltin hydroxide122 (see also Table 8). 

The triorganotin oxides and hydroxides are relatively straightforward. The complete structure of trimethyltin hydroxide has not yet been determined, but exposure of a solution of trimethyltin chloride to moisture gives the half-hydrolysis product Me3SnCbMe3Sn0H H20, in which trigonal-planar Me3Sn units are alternately bridged by Cl and OH, with rSnO = 212.5(2) and 212.1(2) pm, and rSnCl = 290.7(3) and 289.2(3) pm (Equation (132)).353... 

Transmetalation of the perrhenate/aluminosilsesquioxane cube model with SnMe4 is considerably more exothermic than for the perrhenate/silsesquioxane cube model. A similar grafted trimethyltin fragment is formed, as is MeReOs however, the latter is not liberated. It remains bound to the aluminosilsesquioxane cube via the Lewis acid-base interaction with the A1 center. The optimized structure also contains a Lewis acid-base interaction between Re and an adjacent framework oxygen... 

X-ray methods that the trimethyltin chloride-pyridine complex has a 1 1 composition. It is a molecular adduct of trigonal bipyramidal structure, with three methyls lying on the equatorial plane and with the pyridine and a chlorine atom at the axial positions. The Sn—Cl distance found in the complex exceeds that in the initial halide. 

Trimethyltin chloride and bromide form DMSO complexes of 1 1 composition, melting at 49°C (73) and 63°C (111) respectively. The decrease in V(S=0) (An is 95 cm-1 for Me3SnCI-DMSO, and 45 cm-1 for Me3SnBr Bz2SO) may show7 (88, 77) that the coordination is via the oxygen, whereas the absence of ys(Sn—C) from the complexes of MejSnBr (Table XII) suggests a structure of type la. 

Organotin compounds with intermolecular S=0 — Sn or Se=0 — Sn interactions are relatively rare and only a few single-crystal X-ray crystal structure analyses have been reported. Early examples of coordination are the trimethyltin sulfinates Me3Sn02SR (R = Me, CH2C=CH)113-115 and the corresponding selenates RsSnC SeR (R = Me, Ph)116,117. 

The chloride 299b and the related six-membered carboxylic tin species, in which an intramolecular O — Sn interaction stabilizes the 1,3-diaxial conformations696, were discussed in detail in a review636. The corresponding trimethyltin derivatives in the absence of an O —> Sn coordination exist predominantly as the 1,3-diequatorial conformers. Moreover, an X-ray structure determination of the fluoride 299a, the analogue of 299b, which... 

The single crystal X-ray structure analysis of the trimethyltin-substituted ammonium salt [H2N(SnMe3)2][SnMe3Cl2] (115)247 was also reported. In compound 115 the anion... 

Two recent structure determinations by Schlemper and Britton (Inorg. Chcm. 5, 408, 511 (1966)), show that trimethyltin cyanide is composed of planar (CHj)jSn groups which are strong into linear chains by CN bridges. They also show that the corresponding germanium compound (see section IIA) is molecular with the primary and possible only from possessing the normal cyanide structure. 

The development of the hypervalency concept was discussed in general. This model was concerned with the group 14 elements . The ability of the tin atom to expand the coordination sphere in organotin compounds was established in the early 1960s, when an oligomeric structure was suggested for trimethyltin fluoride and trimethyltin carboxylates" on the basis of IR data. It should be pointed out that the trimethyltin chloride-pyridine adduct was the first pentacoordinate organotin compound structurally characterized by X-ray diffraction in 1963". ... 

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