Studies in aryltin chemistry

Gold–Silane and Gold–Stannane Complexes: Saturated Molecules as σ‐Acceptor Ligands

“…Consistently, the signal in the 119 Sn NMR spectrum appears as a triplet at À147 ppm ( 3 J119 Sn-P = 56 Hz). This chemical shift is at distinctly lower frequency than those of tetracoordinate Ar 3 SnF derivatives (d = À65 to À85 ppm) [25] but approaches those reported for related nitrogen adducts (d = À195 to À200 ppm). [26] This finding suggests an increase in the coordination number of the tin atom and thus the presence of a gold!stannane interaction.…”

“…The F and Au atoms define the apical axis (F-Sn-Au 176.27(9)8), while the three C atoms occupy the basal positions (S(C-Sn-C) 359.98). The SnÀF bond length (2.018(3) ) significantly surpasses those of tetracoordinate Ar 3 SnF compounds (1.96-1.97 ) [25] and falls in the same range as their nitrogen adducts (2.02 ). [26] These geometric features indicate that tin is more strongly bound to gold than silicon.…”

Products of hydrolysis of C,N-chelated triorganotin(IV) chlorides and use of products as catalysts in transesterification reactions

“…The Sn-O-Sn angle measured in the X-ray structure is 136.02(8)°, similar to the value found in bis(triphenylstannyl)oxide (137.3°) [21] and in agreement with the value calculated from the NMR spectrum in solution (vide supra). In comparison, the values found for this angle in the case of analogous compounds bearing o-anisyl-or o-tolyl-ligands are significantly higher (167.0° [9] and 180.0° [18]). It is worth to mention here, that a related structure of an ionic hydrolysis products of L CN Me 2 SnI was reported very recently, [L CN Me 2 Sn-(OH)-SnMe 2 L CN ] + I À , two L CN Me 2 Sn units bridged by one single OH group forming the cation whereas the iodine acts as counter-anion [22].…”

“…According to the literature, the major parameter in the structural evaluation of bis(triorganotin) oxides, also known as stannoxanes (R 3 SnOSnR 3 ), is the interatomic Sn-O-Sn angle. Generally, the presence of bulkier substituent groups on tin leads to higher angle values [9]. The further reaction of these compounds with inorganic carbonates or carbon dioxide leading to organotin(IV) carbonates or organic carbonates has been reported as well [4a,10].…”

Triorganotin Fluoride Structures: A Ligand Close‐Packing Model with Predominantly Ionic Sn−F Bonds

“…The tensor analyses were performed according to the method developed by Herzfeld and Berger; [64] [65] WINFIT software (Bruker) was used to analyze the spectra. [86] The principle components of the shielding tensors are reported using Haeberlen's notation as the isotropic chemical shift (δ iso ϭ Ϫσ iso ), the anisotropy (ζ ϭ σ 33 Ϫ σ iso ) and the asymmetry (η ϭ |σ 22 Ϫ σ 11 |/|σ 33 Ϫ σ iso |), σ 11 , σ 22 , σ 33 are the three components of the shielding tensor expressed in its principal axis system with the following convention: |σ 33 Ϫ σ iso | Ն |σ 11 Ϫ σ iso | Ն |σ 22 Ϫ σ iso |. [87] With this convention, ζ is a signed value expressed in ppm and η is a dimensionless parameter, the value of which varies between 0 and 1.…”