Synthesis of HeavyN‐Heterocyclic Tetrylenes: Influence of Ligand Sterics on Structure

Abstract

The synthesis and structural characterisation of [(NONR)M] (NON=O(SiMe2NR)2]2−; R=tBu, Ph, 2,6‐Me2C6H3 (Dmp), 2,6‐iPr2C6H3 (Dipp); M=Ge, Sn, Pb) is described. Germanium complexes [(NONPh)Ge], [(NONDmp)Ge] and [(NONDipp)Ge] are monomeric. Tin complexes [(NONPh)Sn]2, [(NONDmp)Sn]2 and [(NONtBu)Sn]2 are dimeric in the solid‐state, with [(NONPh)Sn]2 forming a link through bridging N‐atoms, [(NONDmp)Sn]2 linked through Sn⋅⋅⋅Ar contacts and [(NONtBu)Sn]2 forming the first distannene bearing two amido ligands. In contrast, [(NONDipp)Sn] is monomeric in the solid‐state. The lead complexes [(NONPh)Pb]2 and [(NONDmp)Pb]2 are isostructual with their tin analogues while [(NONtBu)Pb] is monomeric in the solid‐state. Solution phase NMR spectroscopic data suggest that all [(NONR)M] compounds are monomeric in solution. Structural parameters, including buried volume (%Vbur) are discussed.

A complete series of N-heterocyclic tetrylenes (Si–Pb) with a 1,1′-ferrocenediyl backbone enabled by 1,3,2-diazaborolyl N-substituents

“…101.88(8)°. 28 In line with the bulky nature of {B}, the corresponding bond angles of 1E are exceptionally large, too, being already similar to those of the acyclic congeners (Me 3 SiN{B}) 2 E.…”

Synthesis, Characterization, and Structural Analysis of AM[Al(NONDipp)(H)(SiH2Ph)] (AM = Li, Na, K, Rb, Cs) Compounds, Made Via Oxidative Addition of Phenylsilane to Alkali Metal Aluminyls

“…However, in the cationic moiety, the outer THF-solvated Rb cations also bond to the O-atom of the adjacent NON Dipp -ligands, to propagate the polymeric cation–anion arrangement of 2 . The interaction of the oxygen atom with additional cations is not common for the NON R ligand, 28 with the oxygen typically adopting a purely structural role in the ligand backbone.…”

“…As both Rb1 and Rb3 are located on an inversion center, these atoms each engage in a total of 4 × Rb•••H and 2 × Rb•••π(arene) interactions, with no direct bonding to the THF. However, in the cationic moiety, the outer THF-solvated Rb cations also bond to the O-atom of the adjacent NON Dipp -ligands, to propagate the polymeric cation− anion arrangement of 2.The interaction of the oxygen atom with additional cations is not common for the NON R ligand,28 with the oxygen typically adopting a purely structural role in the ligand backbone.…”

Disproportionation of Sn(ii){CH(SiMe3)2}2 to ˙Sn(iii){CH(SiMe3)2}3 and ˙Sn(i){CH(SiMe3)2}: characterization of the Sn(i) product

“…A single 119 Sn NMR signal is displayed at d = +225.9 ppm (scan width = +3500 to À550 ppm), indicating magnetic equivalence of all Sn atoms, and displays very weak 1 J( 119 Sn-117 Sn) coupling (210.7 Hz). This signal is shifted far upfield from other stannylenes, 38,39 due to the greater shielding effect of the 6-Sn core, (for example, 1 displays a 119 Sn NMR signal at d = +2328 ppm). 40 31 and an expected upfield signal for the BDI Dip Mg-CH(SiMe 3 ) 2 proton (d = À1.59 ppm).…”

“…A single 119 Sn NMR signal is displayed at δ = +225.9 ppm (scan width = +3500 to −550 ppm), indicating magnetic equivalence of all Sn atoms, and displays very weak 1 J ( 119 Sn– 117 Sn) coupling (210.7 Hz). This signal is shifted far upfield from other stannylenes, 38,39 due to the greater shielding effect of the 6-Sn core, (for example, 1 displays a 119 Sn NMR signal at δ = +2328 ppm). 40 Similar 119 Sn NMR signals have been observed for clusters including Schulz's Sn 10 (Trip) 8 , for which 3 individual 119 Sn signals were observed at δ = +358.9, +236.7 and +134.7 ppm, indicating magnetically inequivalent Sn atoms within the structure.…”