- Phenylselenolate mercury alkyl compounds, PhSeHgMe and PhSeHgEt: Molecular structures, protolytic Hg-C bond cleavage and phenylselenolate exchange
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The phenylselenolate mercury alkyl compounds, PhSeHgMe and PhSeHgEt, have been structurally characterized by X-ray diffraction, thereby demonstrating that both compounds are monomeric with approximately linear coordination geometries; the mercury centers do, nevertheless, exhibit secondary Hg...Se intermolecular interactions that serve to increase the coordination number in the solid state. The ethyl derivative, PhSeHgEt, undergoes facile protolytic cleavage of the Hg-C bond to release ethane at room temperature, whereas PhSeHgMe exhibits little reactivity under similar conditions. Interestingly, the cleavage of the Hg-C bond of PhSeHgEt is also more facile than that of the thiolate analog, PhSHgEt, which demonstrates that coordination by selenium promotes protolytic cleavage of the mercury-carbon bond. The phenylselenolate compounds PhSeHgR (R = Me, Et) also undergo degenerate exchange reactions with, for example, PhSHgR and RHgCl. In each case, the alkyl groups preserve coupling to the 199Hg nuclei, thereby indicating that the exchange process involves metathesis of the Hg-SePh/Hg-X groups rather than metathesis of the Hg-R/Hg-R groups.
- Yurkerwich, Kevin,Quinlivan, Patrick J.,Rong, Yi,Parkin, Gerard
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p. 307 - 314
(2015/12/09)
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- HALOGEN AND PEUDOHALOGEN SUBSTITUTION OF SOME ADAMANTANOID CHALCOGENATE CLUSTERS (2-) USING METHYLMERCURY AND TRIPHENYLTIN DERIVATIVES. A MULTINUCLEAR NUCLEAR MAGNETIC RESONANCE STUDY
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Multinuclear nmr (1H, 77Se, 111/113Cd, 119Sn, 199Hg, as appropriate) has been used to study Y(1-) - EPh(1-) exchange in Me2CO or MeCN between (RnM'Y (RnM' = Ph3Sn or MeHg; Y = Cl, Br, I, NCO, or NCS) and the adamantane-like anions (2-) (E = S, M = Zn, Cd, or Co; E = Se, M = Zn or Cd), as their tetraalkylammonium salts.Quantitative terminal substitution of the clusters occurs in most cases, giving 4-x(MY)x>(2-) (x = 1-4).However, reaction is incomplete for M = Cd, E = S or Se, RnM'Y = Ph3SnNCO or Ph3SnNCS and for M = Zn or Co, E = S, RnM'Y = MeHgI.Differences in the extents of reaction for Ph3SnY and MeHgY are consistent with the position of equilibrium in MeHgY:Ph3SnEPh mixtures.Group interchange provides a convenient alternative synthesis of the known halogen-substituted clusters (2-) (M = Zn or Cd, Y = Cl, Br, or I; M = Co, Y = Cl), and the first syntheses of (2-) (Y = Br or I) and various pseudohalogen-substituted adamantanoid anions.The nuclei used for full direct nmr characterization of the new clusters in solution were: 77Se and 113Cd for 4-x(CdY)x>(2-) (x = 1-4; Y = NCO or NCS); 77Se for 4-x(ZnY)x>(2-) (x = 1-4, Y = NCO or NCS); 113Cd for 4-x(CdY)x>(2-) (x = 1-4; Y = NCO or NCS); 1H for (2-) (Y = Br, I, NCO, or NCS).The first solution 1H nmr spectrum of (2-) is also reported.
- Dean, Philip A. W.,Vittal, Jagadese J.
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p. 2443 - 2451
(2007/10/02)
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