Correlating Mössbauer and Solution- and Solid-State ¹¹⁷Sn NMR Data with X-ray Diffraction Structural Data of Triorganotin 2-[(E)-2-(2-Hydroxy-5-methylphenyl)-1-diazenyl]benzoates

Abstract

A series of R 3 SnO 2 CR′ compounds, where R) Me (1), Et (2), n Bu (3), Ph (4), and cHex (5) and R′CO 2 is the carboxylate residue of 2-[(E)-2-(2-hydroxy-5-methylphenyl)-1-diazenyl]benzoic acid, has been shown by multinuclear magnetic resonance studies to be monomeric in solution. Crystallography shows that monomeric four-coordinate species are found in the solid state for 4 and 5 but polymeric structures with five-coordinate tin atoms are found for 1-3. The different behavior is ascribed to the steric demands of the tin-bound substituents. A fair correlation is found between the difference in 117 Sn chemical shift between the solution and solid states and the carbonyl oxygen-tin distance of the compounds 1-5, only when the data of 4, R) Ph, are omitted. This indicates that the mesomeric effect of the phenyl group does not express its influence to the same extent in the solid and solution states, unlike the inductive effects. By contrast, a good correlation including 4 is found between the Mössbauer quadrupole splitting and the difference in 117 Sn chemical shift between the solution and solid states. This shows that the nature of the organic group on the tin atom contributes to similar extents to the values of the 117 Sn chemical shifts in solution and solid state, independently of the existence or not of mesomeric effects, and that the parallel behavior of QS and 117 Sn chemical shifts is geometry independent.

Tricyclohexyl(3,5-dibromo-2-hydroxybenzoato-κO)tin(IV)

“…The monodentate mode of coordination of the benzoate group is reflected in the disparate O1-C19 and O2-C19 bond lengths of 1.227 (7) and 1.294 (7) Å, respectively. Bond dimensions around Sn atom are similar to those found in the structures of tricyclohexyltin benzoates such as tricyclohexyl(4-hydroxylbenzoato)tin (Song et al, 2002) and tricyclohexyl[2-(2-(2-hydroxy-5-methylphenyl)-1-diazenyl)benzoato]tin (Willem et al, 1998). An intramolecular O-H···O hydrogen bond is found between the carboxyl O1 atom and the phenolic hydroxy group (Fig.…”

“…For related structures, see : Baul et al (2001); Rauf et al (2008); Smith et al (1986); Song et al (2002); Wang et al (2007); Willem et al (1998).…”

Crystal structure of trimesityltin(IV)benzoate, (C27H33)3Sn(O2CC6H5)

“…The structural chemistry of the triorganotin carboxylates has been reviewed and is known to have a wide variety of structures, including monomelic, to oligomeric and polymeric motifs [2]. Steric effects, associated with Sn-and/or ligand-based substituents have been found responsible for dictating the nature of the structure in the solid state [3]. The present structure, with large Sn-bound mesityl groups is monomelic in accord with these conclusions.…”

Amino acetate functionalized Schiff base organotin(IV) complexes as anticancer drugs: synthesis, structural characterization, and in vitro cytotoxicity studies

“…This is also reflected in 1 J( 13 C-119/117 Sn) coupling constants (see experimental) and the values are unambiguously characteristic for four-coordinate tin atoms [63]. These results demonstrate that the polymeric structure with five-coordinate tin atoms found in the solid state is lost upon dissolution (see below for the crystal structure discussion).…”

“…in CDCl 3 exhibit a single sharp 119 Sn resonance in the range -83 to -103 ppm, suggesting that the Sn-atoms in the complexes have the same four-coordinate environment [42,47,49,62,63]. This is also reflected in 1 J( 13 C-119/117 Sn) coupling constants (see experimental) and the values are unambiguously characteristic for four-coordinate tin atoms [63].…”