1609207-84-2Relevant academic research and scientific papers
Intramolecularly coordinated (6-(Diphenylphosphino)acenaphth-5-yl) stannanes. Repulsion vs attraction of P- and Sn-containing substituents in the peri positions
Hupf, Emanuel,Lork, Enno,Mebs, Stefan,Beckmann, Jens
, p. 2409 - 2423 (2014)
The intramolecularly coordinated (6-(diphenylphosphino)acenaphth-5-yl) stannanes ArSnBu3 (1), ArSnPh3 (2), ArSnPh2Cl (3), ArSnPhCl2 (4), ArSnCl3 (5), Ar2SnCl 2 (6), ArSnPh2O3SCF3 (7), and ArSnPh2F (8) were synthesized and fully characterized by multinuclear NMR spectroscopy (119Sn, 31P, 19F, 13C, 1H) and X-ray crystallography (Ar = 6-Ph 2P-Ace-5-). Due to the different substituents, the Lewis acidities of the Sn atoms of 1-8 vary substantially, which is reflected in the different P-Sn peri distances lying in the range from 2.7032(9) to 3.332(2) A. In MeCN, 7 undergoes electrolytic dissociation into solvated triarylstannyl cations and triflate anions. The gas-phase structures of 2-5, 8, and the triarylstannyl cations ArPh2Sn+ (7a) and [ArPh2Sn· NCMe]+ (7b) were obtained by geometry optimization at the B3PW91/TZ level of theory. A detailed analysis of a set of real-space bonding indicators (RSBI) derived from the electron and pair densities following the atoms in molecules (AIM) and electron localizability indicator (ELI-D) topological approaches, respectively, uncovers the Sn-P peri interaction in 2 to be in the border regime between nonbonding and weakly ionic. With an increasing number of Cl atoms attached to the Sn atom, the Sn-P bond becomes considerably shorter and exhibits a decreasingly polar covalent interaction. As expected, this trend is significantly enhanced for the Sn-P interactions in the charged compounds 7a,b. The Sn-P bond properties of 8, however, very much resemble those of 3, which means that the electronic impact of the F atom in the axial position is comparable to that of the axial Cl atom.
