Reactivity of Bis(2,2,5,5-tetramethyl-2,5-disila-1-azacyclopent-1-yl)tin with CO₂, OCS, and CS₂ and Comparison to That of Bis[bis(trimethylsilyl)amido]tin

Abstract

The heterocumulenes carbon dioxide (CO(2)), carbonyl sulfide (OCS), and carbon disulfide (CS(2)) were treated with bis(2,2,5,5-tetramethyl-2,5-disila-1-azacyclopent-1-yl)tin {[(CH(2))Me(2)Si](2)N}(2)Sn, an analogue of the well-studied bis[bis(trimethylsilyl)amido]tin species [(Me(3)Si)(2)N](2)Sn, to yield an unexpectedly diverse product slate. Reaction of {[(CH(2))Me(2)Si](2)N}(2)Sn with CO(2) resulted in the formation of 2,2,5,5-tetramethyl-2,5-disila-1-oxacyclopentane, along with Sn(4)(μ(4)-O){μ(2)-O(2)CN[SiMe(2)(CH(2))(2)]}(4)(μ(2)-N═C═O)(2) as the primary organometallic Sn-containing product. The reaction of {[(CH(2))Me(2)Si](2)N}(2)Sn with CS(2) led to formal reduction of CS(2) to [CS(2)](2-), yielding [{[(CH(2))Me(2)Si](2)N}(2)Sn](2)CS(2){[(CH(2))Me(2)Si](2)N}(2)Sn, in which the [CS(2)](2-) is coordinated through C and S to two tin centers. The product [{[(CH(2))Me(2)Si](2)N}(2)Sn](2)CS(2){[(CH(2))Me(2)Si](2)N}(2)Sn also contains a novel 4-membered Sn-Sn-C-S ring, and exhibits a further bonding interaction through sulfur to a third Sn atom. Reaction of OCS with {[(CH(2))Me(2)Si](2)N}(2)Sn resulted in an insoluble polymeric material. In a comparison reaction, [(Me(3)Si)(2)N](2)Sn was treated with OCS to yield Sn(4)(μ(4)-O)(μ(2)-OSiMe(3))(5)(η(1)-N═C═S). A combination of NMR and IR spectroscopy, mass spectrometry, and single crystal X-ray diffraction were used to characterize the products of each reaction. The oxygen atoms in the final products come from the facile cleavage of either CO(2) or OCS, depending on the reacting carbon dichalogenide.

Insertion Reactions of Heterocumulenes with Zincocene Cp*2Zn

“…Unfortunately, the 13 C{ 1 H} NMR spectra of 4 and 5 did not exhibit resonances for the C S 2 carbon atoms, which were expected to be shifted to lower field compared to that of free CS 2 ( δ =192.6 ppm). Comparable findings were recently reported 22. Typically, values far above 200 ppm were reported,22,23 even though Limberg et al very recently observed a resonance at δ = 172.5 ppm for a dinuclear Cu‐CS 2 complex 24…”

“…Comparable findings were recently reported 22. Typically, values far above 200 ppm were reported,22,23 even though Limberg et al very recently observed a resonance at δ = 172.5 ppm for a dinuclear Cu‐CS 2 complex 24…”

Modern concepts and methods in the chemistry of polyhedral metallasiloxanes

“…35), such as an azoimide residue (99 [144]), amino group (100 [145]), acyl group (101 [146]), halogen (102 [147]), organophosphine (103 [148]), or isothiocyanate group (104 [149]. 103 [148] 104 [149] This is also true for the formation of polyhedral molecules containing only alkali metal ions, where these PHMSs are formed exclusively from organosilanolates (Fig. 36, 105 [150]), or with additional ligands such as alkoxy groups (Fig.…”

CO2 as an Oxygen Source for Polysiloxanes – Preparation, Crystal Structure and Thermal Decomposition of Two Novel Silylcarbamates

“…Most of these reports focus on the reactions of Me 3 SiCl with primary and secondary amines, e. g. using the TMS substituent as directing group in organic synthesis [19]. In contrast, we report here the use of Me 2 SiCl 2 and a primary amine as starting materials for the synthesis of diaminosilanes Me 2 Si(NHR) 2 .…”

“…Hence, CO 2 is mainly used as a C1 source. One of the several methods known for the activation of CO 2 [2] is the insertion into a main group or transition metal nitrogen bond [3].…”