440117-80-6Relevant academic research and scientific papers
Reversible Coordination of H2 by a Distannyne
Wang, Shuai,Sherbow, Tobias J.,Berben, Louise A.,Power, Philip P.
supporting information, p. 590 - 593 (2018/01/26)
The terphenyl tin(II) hydride [AriPr4Sn(μ-H)]2 (1) (AriPr4 = C6H3-2,6(C6H3-2,6-iPr2)2) was shown to form an equilibrium with the distannyne AriPr4SnSnAriPr4 (2) and H2 in toluene at 80 °C. The equilibrium constant and Gibbs free energy for the dissociation of H2 are 2.23 × 10-4 ± 4.9% and 5.89 kcal/mol ± 0.68%, respectively, by 1H NMR spectroscopy and 2.33 × 10-4 ± 6.2% and 5.86 kcal/mol ± 0.73%, respectively, by UV-vis spectroscopy, indicating that the hydride 1 is strongly favored. Further heating of 2 at ca. 100 °C afforded the known pentagonal-bipyramidal Sn7 cluster Sn5(SnAriPr4)2 (3). Mechanistic studies show that 3 is formed from distannyne 2, which is generated from 1. The order of the reaction for the conversion of 2 into 3 was found to be zero, and the rate constant is 1.77 × 10-5 M s-1 at 100 °C. Hydride 1 was further characterized by cyclic voltammetry, and its pKa was found to be 18.8(2) via titration with 1,8-diazabicyclo[5.4.0]undec-7-ene. The bond dissociation free energy was estimated to be 51.1 kcal/mol ± 3.4% on the basis of its pKa and reduction potential. Studies with deuterium indicate ready exchange of D2 with the hydrides in 1.
Reaction of a diaryldigermyne with ethylene
Sasamori, Takahiro,Sugahara, Tomohiro,Agou, Tomohiro,Sugamata, Koh,Guo, Jing-Dong,Nagase, Shigeru,Tokitoh, Norihiro
, p. 5526 - 5530 (2015/09/28)
Reaction of the stable digermyne BbtGeGeBbt (Bbt = 2,6-[CH(SiMe3)2]2-4-[C(SiMe3)3]-C6H2) with ethylene initially afforded the corresponding 1,2-digermacyclobutene. Depending on t
Reversible complexation of isocyanides by the distannyne Ar′SnSnAr′ (Ar′ = C6H3-2,6(C 6H3-2,6-iPr2)2)
Peng, Yang,Wang, Xinping,Fettinger, James C.,Power, Philip P.
, p. 943 - 945 (2010/06/12)
The reaction of the distannyne Ar′SnSnAr′ (Ar′ = C 6H3-2,6(C6H3-2,6-iPr 2)2) with tert-butyl or mesityl isocyanide afforded the bis-adducts Ar′SnSnAr′(CNBut)2/su
Germanium and tin analogues of alkynes and their reduction products
Pu, Lihung,Phillips, Andrew D.,Richards, Anne F.,Stender, Matthias,Simons, Richard S.,Olmstead, Marilyn M.,Power, Philip P.
, p. 11626 - 11636 (2007/10/03)
The reduction of terphenylgermanium(II) or terphenyltin(II) chlorides with alkali metals was investigated. Treatment of Ar′GeCl or Ar*GeCl (Ar′ = C6H3-2,6-Dipp2, Dipp = C 6H3-2,6-Pri2; Ar* = C 6H3-2,6-Trip2, Trip = C6H 2-2,4,6-Pri3) with lithium, sodium, or potassium afforded the neutral alkyne analogues Ar′GeGeAr′, 1, Ar*GeGeAr*, 2, the singly reduced radical species NaAr*GeGeAr*, 3, or KAr′GeGeAr′, 4, or the doubly reduced compounds Li2Ar′GeGeAr′, 5, Na 2Ar*GeGeAr*, 6, or K2Ar*GeGeAr*, 7. Similarly, reduction of Ar′SnCl or Ar*SnCl afforded the neutral Ar′SnSnAr′, 8, or Ar*SnSnAr*, 9, the radical anions [(THF)3Na{Ar*SnSnAr*}], 10, [K(THF) 6][Ar′SnSnAr′], 11, [K(THF)6][Ar* SnSnAr*], 12, [K(18-crown- 6)(THF)2] [Ar*SnSnAr*], 13, or the doubly reduced Na2Ar*SnSnAr*, 14, K 2Ar′SnSnAr′, 15, or K2Ar*SnSnAr*, 16. The compounds were characterized by UV-vis, 1H and 13C NMR or EPR spectroscopy. The X-ray crystal structures of all compounds were determined except those of 2 and 9. The neutral 1 and 8 displayed planar, trans-bent CMMC (M = Ge and Sn) cores with M-M-C angles of 128.67(8) and 125.24(7)°, respectively. The M-M bond lengths, 2.2850(6) and 2.6675(4)A, indicated considerable multiple character and a bond order approaching two. Single and double reduction of the neutral species resulted in the narrowing of the M-M-C angles by ca. 12-32° and changes in the Ge-Ge and Sn-Sn bond lengths. One-electron reduction afforded a slight (ca. 0.03-0.05A) lengthening of the Ge-Ge bonds in the case of germanium species 3 and 4 and a greater lengthening (ca. 0.13-0.15A) for the Sn-Sn bonds in the tin compounds 10-13. The addition of another electron yielded salts of the formal dianions [Ar′MMAr′]2- and [Ar*MMAr*]2- which are isoelectronic to the corresponding doubly bonded, neutral arsenic and antimony derivatives. All the dianion salts were obtained as contact ion triples with two alkali metal cations complexed between aryl rings. The Ge-Ge bonds in the dianions of 5-7 were longer, whereas the Sn-Sn distances in the dianions in 14, 15, and 16 were shorter than those in the monoanions. Unusually, the Li2Ar′ GeGeAr′ salt, 5, displayed a longer Ge-Ge bond (by ca. 0.06A) than those of its Na+ or K+ analogue salts which was attributed to the greater polarizing power of Li+. It was concluded that the M-M bond lengths in 3-7 and 10-16 are dependent on several factors that include M-M-C angle, Coulombic repulsion, alkali metal cation size, and the character of the molecular energy levels. The M-M bonding in the neutral compounds was accounted for in terms of a second-order Jahn-Teller mixing of σ*- and a π-orbital which afforded bond orders near two for the neutral compounds, 1, 2, 8, and 9. Calculations on MeMMMe (M = Ge or Sn) model species showed that the LUMO corresponded to an orbital that had n+ lone pair character. The slight Ge-Ge bond length increase upon one-electron reduction is consistent with these results, and the further bond lengthening upon double reduction is consistent with increased Coulombic repulsion. The greater Sn-Sn bond length increase seen for one-electron reduction of the tin species is probably due to the increased p-character of orbitals comprising the Sn-Sn σ-bond when the Sn-Sn-C angle is decreased by ca. 30°. Upon further reduction, the slight decrease in the Sn-Sn bond is probably a result of the reduced importance of Coulombic repulsion due to the larger size of tin and a widening of the Sn-Sn-C angles which may shorten the Sn-Sn σ-bond.
Synthesis and characterization of 2,6-Dipp2-H3C6SnSnC6 H3-2,6-Dipp2 (Dipp = C6H3-2,6-Pri2): A tin analogue of an alkyne
Phillips, Andrew D.,Wright, Robert J.,Olmstead, Marilyn M.,Power, Philip P.
, p. 5930 - 5931 (2007/10/03)
The reaction of Sn(Cl)C6H3-2,6-Dipp2 (Dipp = C6H3-2,6-Pri2) with a stoichiometric amount of potassium in benzene affords 2,6-Pri2-H3C6SnSnC6H3-2,6-Pri2 (1) as dark blue-green crystals. The compound 1 is a tin analogue of an alkyne. It was characterized by 1H and 13C NMR and UV-vis spectroscopy, cyclic voltammetry, combustion analysis and X-ray crystallography. The structural data show that 1 has a trans-bent, planar C(ipso)SnSnC(ipso) skeleton with a Sn-Sn bond distance of 2.6675(4) A and a Sn-Sn-C angle of 125.24(7)°. The Sn-Sn distance, which is ca. 0.15 A shorter than a conventional Sn-Sn single bond, and the trans-bent structure indicate the presence Sn-Sn multiple bond character unlike the related singly bonded ArPbPbAr species. Copyright
