Sn-X bonds

The broken bonds (boldface=dissociated atom or group), AfH (R), kcal/mol (kj/mol) BDEs (boldface = recommended data reference in parentheses) Methods  

3-Trimethyl-2-stanna- butane MesSn-iPr 55.4 231.8 Derived 1988GR1/KAM 

3-Tetramethyl-2- stanna-butane MesSn-fBu 50.4 210.9 Derived 1988GR1/KAM 

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The mobility of the franmework of azastanntrane 12 (see Table 5) was analysed by FTIR and NMR spectroscopy125,126. The IR and Raman frequencies of the N—Sn coordination bond in compound 13 are correlated with the Sn—X bond lengths of the various X substituents127. 

It is generally accepted that photolysis of R3SnX (R = alkyl group X = halogen) results in the homolytic cleavage of the Sn—X bond. However, under certain conditions, for example in polar solvents such as EtOH which can act as a Lewis base, the photochemistry can switch to heterolytic cleavage of the Sn—X bond followed by formation of solvent adducts such as R3(X)Sn(Sol) (Sol = solvent)17. 

Although the majority of these complexes contain phosphines as supporting ligands, compounds of platinum(IV) with Pt—Ge and Pt—Sn bonds have been formed by oxidative addition of Ge—X and Sn—X bonds to complexes PtMe2(L—L) (L—L = bipy, phen). Trace... 

The Sn—C bond frequencies are rather less sensitive to electronic effects in methyltin halides and depend weakly on either the number or the nature of the halogens. The increases associated with complex formation are also insignificant. Vibrational spectroscopy is a good tool not only for studying the spatial arrangement and ionicities of Sn—X bonds but also for measur-... 

Together with stereochemical problems, the ways in which the Sn—C and Sn—X bonds are affected on going from a methyltin halide to its molecular complex are of interest. Such information is quite helpful in interpreting the reactivities of methyltin halides in various solvents (110, 117). 

In diorganotin adducts D — SnR2X2 the Sn—X bond length differences between axial and equatorial positions in the pentacoordinate species 118 are of particular interest since they conform quite well to expectations of hypervalent D — Sn—X bonding (Section V.B.3). The longer Sn—Clax bond length by ca 0.06 A due to N — Sn donor interaction is consistent with the expected lower s character of the axial bond compared to... 

Some bond distances and energies of Sn-X bonds are given in Table 2. 

For [Sn Xs] species having a basic trigonal pyramidal geometry, 5 values correlate with the Sn-X bond distance. 

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