Cohydrolysis of Organotin Chlorides with Trimethylchlorosilane. Okawara's Pioneering Work Revisited and Extended

Abstract

The synthesis of the stannasiloxanes and [Cp(CO) 2 Fe] 2 Sn(OSiPh 3 ) 2 (7a), the monoorganotin trichloride Me 3 SiCH 2 SnCl 3 (13), and the organotin oxocluster (Me 3 SiCH 2 -Sn) 12 O 14 (OH) 6 Cl 2 ( 14) is reported. Their identity was confirmed by both solution and solid state multinuclear NMR spectroscopy and in the case of 1, 2, 6, 7a, and 14 also by singlecrystal X-ray analyses. A spinning sideband analysis of the 119 Sn MAS spectra reveals the coordination geometries of the tin atoms in the stannasiloxanes 1 and 2 to be different from those of related diorganotin oxides (R 2 SnO) n (R ) Me, Et). In solution, 1 and 2 exhibit an intramolecular exchange process as well as monomer-dimer equilibria. The reaction of 4 with cyclo-(t-Bu 2 SnO) 3 and of cyclo-[(Me 3 SiCH 2 ) 2 SnO] 3 with cyclo-(t-Bu 2 SnO) 3 provided evidence for the formation in situ of the mixed tetraorganodistannoxane t-Bu 2 (Me 3 SiO)-SnOSn(OSiMe 3 )(CH 2 SiMe 3 ) 2 (10) and of the hexaorganotristannoxanes cyclo-[(Me 3 SiCH 2 ) 2 -Sn(OSnt-Bu 2 ) 2 O] (11) and cyclo-{t-Bu 2 Sn[OSn(CH 2 SiMe 3 ) 2 ] 2 O} (12).

X-Ray Structural Characterization of a Monoorganotin Acid

“…The tin–oxygen bond lengths range from 1.958 to 1.970 Å within the six‐membered ring of 3 ⋅ t BuCH 2 NMe 2 and are comparable with those in known Sn 3 O 3 heterocycles 6, 7. The distances between tin and the axially bonded oxygen atoms (1.968 to 1.977 Å) are in the same range as those in hydroxy‐substituted tin–oxygen clusters 18. The tin–carbon bond lengths (2.145 to 2.156 Å) are similar to those in Tpsi‐substituted tin compounds (Tpsi=(PhMe 2 Si) 3 C) 13a…”

Synthesis, characterization and hydrolytic behavior of new bis(2-pyridylthio)acetate ligand and related organotin(IV) complexes

“…The tin atoms of the asymmetric unit, Sn(1) and Sn (2), are bridged by one carboxylate oxygen of the (pyS) 2 CHCO 2 ligand, while the second bis(2-pyridylthio)acetate is monodentate on Sn(2) via the oxygen atom O(4). Two methyl groups completed the five coordination to the metal ion with a distorted trigonal bipyramidal geometry; the equatorial positions are occupied by two methyl carbons (C(1) and C(2)) and one oxygen (O(3)) and the axial positions O(1) and O(3) 0 for Sn(1) and for Sn (2) (5)Å bond lengths, respectively, as found for the axial Sn-O bonds of the stannasiloxanes ({[R 2 (Me 3 SiO)Sn] 2 O} 2 (R@Me, Et)) derivatives [35].…”

Organotin catalysts in organosilicon chemistry

“…The synthesis of the Sn‐O‐Si bond is feasible under basic conditions, i.e. aqueous ammonia, which promotes the in situ formation of Me 3 SiOH, which subsequently reacts with the organotin …”

“…[9] Further studies illustrated the feasibility of synthesizing stannasiloxanes from co-hydrolysis reactions of organotin chlorides with trialkylchlorosilanes, obtaining a series of compounds: {[R 2 (Me 3 SiO)Sn] 2 3 SiOH, which subsequently reacts with the organotin. [10] Some other good examples of the synthesis of this moiety from alkyltin oxides have also been described: the reaction of [(i-Bu) 3 Sn] 2 O and i-BuSiMePhOH in Et 2 O gives (i-Bu) 3 SnOSi-MePhCH 2 CHMe 2 . [11] Infrared spectroscopy has been widely used to verify Si-O-Sn bonds, specifically the easily distinguishable bands of Sn-O at 720 cm À1 and Si-O at 980 cm À1 .…”