Syntheses and Characterization of Tin(II) Complexes Containing 10-π-Electron Ring Systems

Abstract

The compounds [(i-Pr)2ATI]SnCl (1) and {[(i-Pr)2ATI]Sn}[η5-C5H5)ZrCl2(μ-Cl3)ZrCl2(η5-C5H5)] (2) in which [(i-Pr)2ATI] = N-isopropyl-2-(isopropylamino)troponimine have been prepared and characterized by 1H, 13C, and 119Sn NMR spectroscopies and X-ray crystallography. Compounds 1 and 2 feature heterobicyclic C7N2Sn ring systems with basically three- and two-coordinate tin atoms, respectively. Solid state structures of 1 and 2 show weak Sn···Cl interactions. The 119Sn NMR signal of 2 appears at a significantly lower field compared to that of 1. This is consistent with the reduction in coordination number at the Sn center of 2. The 1H NMR data also provide evidence for the formation of a more symmetric solution species with the removal of Cl- from 1. X-ray structural features of C7N2Sn moiety in [(i-Pr)2ATI]SnCl and the {[(i-Pr)2ATI]Sn}+ cation are very similar. The Sn−N bond distances of {[(i-Pr)2ATI]Sn}+ cation are not indicative of any significant Sn−N multiple bonding. The π-electrons of the C7N2Sn ring system, therefore, appears to be mostly delocalized over nitrogen and carbon atoms.

Reactions of (imidazol-2-ylidene)silver(I) chlorides with group 4 metal containing Lewis acids

“…Unlike the two previously reported examples, the anion [{(g 5 -C 5 H 5 )ZrCl 2 } 2 -(l 2 -Cl) 3 ] À in 4 is disposed about a crystallographic center of symmetry. Nevertheless, the metrical parameters are comparable to those previously reported [15,16].…”

“…5). The anion, [{(g 5 -C 5 H 5 )ZrCl 2 } 2 (l 2 -Cl) 3 ] À , was first prepared by Dias et al [15] as the counter ion of both the N-isopropyl-2-(iso propylamino)troponiminato tin(II) and germanium(II) [16] cations. Unlike the two previously reported examples, the anion [{(g 5 -C 5 H 5 )ZrCl 2 } 2 -(l 2 -Cl) 3 ] À in 4 is disposed about a crystallographic center of symmetry.…”

“…1,3-Bis-(2,4,6-trimethylphenyl)imidazolium chloride and 1,3-bis-(4-bromo-2,6-dimethylphenyl) imidazolium chloride were prepared from stoichiometric amounts of para-formaldehyde, glyoxal, hydrochloric acid and the appropriate substituted aniline (2,4,6-trimethylaniline or 4-bromo-2,6-dimethylaniline) using a modification of the method given by Tilset et al [17] (our preparations were carried out in air using solvents as received rather than the anhydrous and anaerobic conditions described in [15]). 1,3-Bis-(2,4,6-trimethylphenyl)-imidazol-2-ylidene silver(I) chloride (1) was prepared according to Ramnial et al [10].…”

“…Yield 1. 15 A suspension of (g 5 -C 5 H 5 )ZrCl 3 (1.00 g, 3.81 mmol) in dichloromethane (5 mL) was added to a solution of (IMes Br )AgCl (2.20 g, 3.81 mmol) in dichloromethane (10 mL). After stirring at room temperature for 24 h, the mixture was filtered through Celite Ò and the volume of solution reduced to 1 mL.…”

Three‐coordinate divalent Group 14 element derivatives and related compounds

“…Thus, the presence of ligands with donor side arms on the germanium or the tin element can (by transfer of electron density) reduce the deficit on 37 is, to our knowledge, the first example of an intramolecular base stabilized homoleptic dialkylgermylene. Various amino-, phosphino-, thioalkoxy-, alkoxy-and aryloxy-divalent species have also been isolated in monomeric form owing to this method of stabilization; one should mention in particular the studies of Jutzi and co-workers, 28,32,54,71 Veith and coworkers, 15,18,40,66 Parkin and co-workers, 67 Jurkschat and co-workers, 77,78 Dias and co-workers 31,35,42,69,80,81 and Roesky and co-workers. …”