Intramolecularly Coordinated Organotin Tellurides: Stable or Unstable?

Abstract

The step-wise oxidation of an organotin(I) compound with elemental tellurium gave a variety of unprecedented organotin tellurides containing tin atoms in the oxidation states +II and +IV.

The Role of Monoanionic Aryl Pincer Ligands in the Stabilization of Group 14 Metallylenes

“…The bond lengths obtained from solid state data indicate that the tin-chalcogene display distances in the range of single bonds. (See Table 4) [42] The Sn-N distances display values between 2.520 and 2.685 Å in all three cases, presenting no significant variation from the values found in the distannyne 44. [40] When Se was used as oxidizing agent, a longer reaction time led to organotin(IV) selenide 49, containing the Sn-Se-Sn moiety and two terminal Sn=Se bonds.…”

“…[40] When Se was used as oxidizing agent, a longer reaction time led to organotin(IV) selenide 49, containing the Sn-Se-Sn moiety and two terminal Sn=Se bonds. [41] The formation of analogous compounds were evidenced in the case of sulphur and tellurium, the organotin(IV) polysulfide 48, [40,43] its formation explained through a sulphide intermediate and tellurium, derivative 50 [42] , as shown in Scheme 9. Compound 50 was revealed to be unstable, decomposing to 52, while in the presence of moisture gave the stannaoxane 53.…”

“…In the case of tellurium, the unsymmetrical compound 51 was also obtained, containing tin atoms in both +II and +IV oxidation states. [42] DFT calculations on the tellurium containing derivatives showed highly positive charges on the tin atoms stabilized through the intramolecular coordination of the N,C,N-pincer ligand. [42] Derivative 44 in reaction with diorgano disulfides formed the corresponding organotin(II) thio derivatives.…”

“…The formation of these compounds was explained through a two-step oxidation followed by the cleavage of the Sn-Sn bond. All the stable tin(II) chalcogenides 45 (E = S), [40] 46 (E = Se), [41] 47 (E = Te) [42] were characterized by NMR spectroscopy and X-ray diffraction, revealing the structural characteristics of divalent tin species. The bond lengths obtained from solid state data indicate that the tin-chalcogene display distances in the range of single bonds.…”

Rational Syntheses and Serendipity: Complexes [LSnPtCl2(SMe2)]2, [{LSnPtCl(SMe2)}2SnCl2], [(LSn)3(PtCl2)(PtClSnCl){LSn(Cl)OH}], and [O(SnCl)2(SnL)2] with L=MeN(CH2CMe2O)2

“…For the DFT calculations, Gaussian 09 with the pure functional BP86 and the def2‐TZVP basis set was used for the geometry optimization. This combination has already successfully been employed for similar compounds . The NBO analyses were performed with NBO6.0 with BP86/def2‐SVP since double‐zeta basis sets give more reliable results for these types of compounds.…”