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1.
Diorganodiselenide [2-(Et2NCH2)C6H4]2Se2 (1) was obtained by hydrolysis/oxidation of the corresponding [2-(Et2NCH2)C6H4]SeLi derivative. The treatment of [2-(Et2NCH2)C6H4]2Se2 with elemental sodium in THF resulted in [2-(Et2NCH2)C6H4]SeNa (2). Reactions between alkali metal selenolates [2-(R2NCH2)C6H4]SeM′ (R = Me, Et; M′ = Li, Na) and MCl2 (M = Zn, Cd) in a 2:1 molar ratio resulted in the [2-(R2NCH2)C6H4Se]2M species [R = Me, M = Zn (3), Cd (4); R = Et, M = Zn (5), Cd (6)]. The new compounds were characterized by multinuclear NMR (1H, 13C, 77Se, 113Cd) and mass spectrometry. The crystal and molecular structures of 1, 3 and 4 revealed monomeric species stabilized by N → Se (for 1) and N → M (for 3 and 4) intramolecular interactions.  相似文献   

2.
A facile synthesis of the novel selenium-capped trimolybdenum and tritungsten ring carbonyl clusters [Se2M3(CO)10]2− (M = Mo, 1; W, 4) have been achieved. The selenium-capped trimolybdenum cluster compound [Et4N]2[Se2Mo3(CO)10] ([Et4N]2[1]) can be obtained from the reaction of the trichromium cluster compound [Et4N]2[Se2Cr3(CO)10] with 4 equiv. of Mo(CO)6 in refluxing acetone. On the other hand, when [Et4N]2[Se2Cr3(CO)10] reacted with 4 equiv. of W(CO)6 in refluxing acetone, the planar cluster compound [Et4N]2[Se2W4(CO)18] ([Et4N]2[3]) was isolated, which could further transform to the tritungsten cluster compound [Et4N]2[Se2W3(CO)10] ([Et4N]2[4]) in good yield. Alternatively, clusters 1 and 4 could be formed from the reactions of the monosubstituted products [Et4N]2[Se2Cr2M(CO)10] (M = Mo; W, [Et4N]2[2]) with 3 equiv. of M(CO)6 in acetone, respectively. Complexes 1-4 are fully characterized by IR, 77Se NMR spectroscopy, and single-crystal X-ray analysis. Clusters 1, 2, and 4 are isostructural and each display a trigonal bipyramidal structure with a homometallic M3 ring (M = Mo, 1; W, 4) or a heterometallic Cr2W ring that is further capped above and below by μ3-Se atoms. Further, the intermediate planar complex 3 exhibits a Se2W2 square with each Se atom externally coordinated to one W(CO)5 group. This paper describes a systematic route to a series of selenium-capped trimetallic carbonyl clusters and the formation and the structural features of the resultant clusters are discussed.  相似文献   

3.
Schiff base N,N′-bis(salicylidene)-p-phenylenediamine (LH2) complexed with Pt(en)Cl2 and Pd(en)Cl2 provided [Pt(en)L]2 · 4PF6 (1) and Pd(Salen) (2) (Salen = N,N′-bis(salicylidene)-ethylenediamine), respectively, which were characterized by their elemental analysis, spectroscopic data and X-ray data. A solid complex obtained by the reaction of hexafluorobenzene (hfb) with the representative complex 1 has been isolated and characterized as 3 (1 · hfb) using UV–Vis, NMR (1H, 13C and 19F) data. A solid complex of hfb with a reported Zn-cyclophane 4 has also been prepared and characterized 5 (4 · hfb) for comparison with complex 3. The association of hfb with 1 and 4 has also been monitored using UV–Vis and luminescence data.  相似文献   

4.
Ph2SiCl2 and PhMeSiCl2 react with Li2E (E = S, Se, Te) under formation of trimeric diorganosilicon chalcogenides (PhRSiE)3 (R = Ph: 1a-3a, R = Me: cis/trans-4a (E = S), cis/trans-5a (E = Se)). In case of E = S, Se dimeric four-membered ring compounds (PhRSiE)2 (R = Ph: 1b-2b, R = Me: cis/trans-4b (E = S), cis/trans-5b (E = Se)) have been observed as by-products. 1a-5b have been characterized by multinuclear NMR spectroscopy (1H, 13C, 29Si, 77Se, 125Te). Four- and six-membered ring compounds differ significantly in 29Si and 77Se chemical shifts as well as in the value of 1JSiSe.The molecular structures of 2a, 3a and trans-5a reported in this paper are the first examples of compounds with unfused six-membered rings Si3E3 (E = Se, Te). The Si3E3 rings adopt twisted boat conformations. The crystal structure of 3a reveals an intermolecular Te-Te contact of 3.858 Å which yields a dimerization in the solid state.  相似文献   

5.
Complexes M(CCCSiMe3)(CO)2Tp′ (Tp′ = Tp [HB(pz)3], M = Mo 2, W 4; Tp′ = Tp [HB(dmpz)3], M = Mo 3) are obtained from M(CCCSiMe3)(O2CCF3)(CO)2(tmeda) (1) and K[Tp′].Reactions of 2 or 4 with AuCl(PPh3)/K2CO3 in MeOH afforded M{CCCAu(PPh3)}(CO)2Tp′ (M = Mo 5, W 6) containing C3 chains linking the Group 6 metal and gold centres.In turn, the gold complexes react with Co33-CBr)(μ-dppm)(CO)7 to give the C4-bridged {Tp(OC)2M}CCCC{Co3(μ-dppm)(CO)7} (M = Mo 7, W 8), while Mo(CBr)(CO)2Tp and Co33-C(CC)2Au(PPh3)}(μ-dppm)(CO)7 give {Tp(OC)2Mo}C(CC)2C{Co3(μ-dppm)(CO)7} (9) via a phosphine-gold(I) halide elimination reaction. The C3 complexes Tp′(OC)2MCCCRu(dppe)Cp (Tp′ = Tp, M = Mo 10, W 11; Tp′ = Tp, M = Mo 12) were obtained from 2-4 and RuCl(dppe)Cp via KF-induced metalla-desilylation reactions. Reactions between Mo(CBr)(CO)2Tp and Ru{(CC)nAu(PPh3)}(dppe)Cp (n = 2, 3) afforded {Tp(OC)2Mo}C(CC)n{Ru(dppe)Cp} (n = 2 13, 3 14), containing C5 and C7 chains, respectively. Single-crystal X-ray structure determinations of 1, 2, 7, 8, 9 and 12 are reported.  相似文献   

6.
Novel square-planar compounds [M(NC5H4CCH)2(dppp)](OTf)2 (M = Pd (1), Pt (2)), [Pt(CCC6H4CN)2(dppp)] (3) and [Pt(C6H4CCC5H4N)2(dppp)] (4) (dppp = 1,3-bis(diphenylphosphino)propane) were prepared and characterised. Their potential as building blocks in the generation of heterobimetallic squares was studied. The reaction of 4 and the ditopic acceptor species [Pd(H2O)2(dppf)](OTf)2 enabled a tetrametallic metallocycle containing two platinum and two palladium atoms to be obtained. The crystal X-ray structure of 4 shows that the Pt?N vectors are nearly perpendicular, and confirm the suitability of the compound to act as a corner unit for the construction of molecular squares.  相似文献   

7.
Syntheses of [Me3SbM(CO)5] [M = Cr (1), W (2)], [Me3BiM(CO)5] [M = Cr (3), W (4)], cis-[(Me3Sb)2Mo(CO)4] (5), [tBu3BiFe(CO)4] (6), crystal structures of 1-6 and DFT studies of 1-4 are reported.  相似文献   

8.
To study the Ru-M interactions and their effects on 31P NMR, complexes [Ru(CO)3(Ph2Ppy)2] (py = pyridine) (1) and [Ru(CO)3(Ph2Ppy)2MCl2] (M = Zn, 2; Cd, 3; Hg, 4) were calculated by density functional theory (DFT) PBE0 method. Moreover, the PBE0-GIAO method was employed to calculate the 31P chemical shifts in complexes. The calculated 31P chemical shifts in 1-3 follow 2 > 3 > 1 which are consistent to experimental results, proving that PBE0-GIAO method adopted in this study is reasonable. This method is employed to predict the 31P chemical shift in designed complex 4. Compared with 1, the 31P chemical shifts in 2-4 vary resulting from adjacent Ru-M interactions. The Ru → M or Ru ← M charge-transfer interactions in 2-4 are revealed by second-order perturbation theory. The strength order of Ru → M interactions is the same as that of the P-Ru → M delocalization with Zn > Cd > Hg, which coincides with the order of 31P NMR chemical shifts. The interaction of Ru → M, corresponding to the delocalization from 4d orbital of Ru to s valence orbital of M2+, results in the delocalization of P-Ru → M, which decreases the electron density of P nucleus and causes the downfield 31P chemical shifts. Except 2, the back-donation effect of Ru ← M, arising from the delocalization from s valence orbital of M2+ to the valence orbital of Ru, is against the P-Ru → M delocalization and results in the upfield 31P chemical shifts in 4. Meanwhile, the binding energies indicate that complex 4 is stable and can be synthesized experimentally. However, as complex [Ru(CO)3(Ph2Ppy)2HgCl]+5 is more stable than 4, the reaction of 1 with HgCl2 only gave 5 experimentally.  相似文献   

9.
Mononuclear complexes of the type, M(CO)4[Se2P(OR)2] (M = Mn, R = iPr, 1a; Et, 1b; M = Re, R = iPr, 3a; Et, 3b) can be prepared from either [-Se(Se)P(OiPr)2]2 (A) or [Se{-Se(Se)P(OEt)2}2] (B) with M(CO)5Br. O,O′-dialkyl diselenophosphate ([(RO)2PSe2]-, abbreviated as dsep) ligands generated from A and B act as a chelating ligand in these complexes. Upon refluxing in acetonitrile, these mononuclear complexes yield dinuclear complexes with a general formula of [M2(CO)6{Se2P(OR)2}2] (M = Mn, R = iPr, 2a; Et, 2b; M = Re, R = iPr, 4a; Et, 4b). Dsep ligands display a triconnective, bimetallic bonding mode in the dinuclear compounds and this kind of connective pattern has never been identified in any phosphor-1,1-diselenoato metal complexes. Compounds 2b, 3b, and 4 are structurally characterized. Compounds 2b and 3b display weak, secondary Se?Se interactions in their lattices.  相似文献   

10.
2-(Azidomethyl)phenyl isocyanide, 2-(CH2N3)C6H4NC (AziNC), coordinates to some cationic Pt(II) and Pd(II) species to afford isocyanide complexes of the type trans-[MCl(AziNC)(PPh3)2][BF4] (M=Pt, l; Pd, 2). AziNC is coordinated also in some neutral Pt(II) and Pd(II) species such as [MCl2(AziNC)2] (M=Pt, 3; Pd, 4) derived from the reactions of 2 equiv. of AziNC with [PtCl2(COD)] and [PdCl2(MeCN)2], respectively. Complexes 1 and 2 react with 1 equiv. of PPh3 affording the heterocyclic carbene complexes trans-[MCl{(H)}(PPh3)2][BF4] (M=Pt, 5; Pd, 6). Complexes 3 and 4 react with 1 equiv. of PPh3 displacing the isocyanide with the formation of the complexes cis-[MCl2(AziNC)(PPh3)] (M=Pt, 7; Pd, 8). These latter ones react with 2 equiv. of PPh3 affording as the final products the cationic carbene species trans-[MCl{(H)}(PPh3)2][Cl] (M=Pt, 9; Pd, 10). Complex 5 was also characterized by single crystal X-ray diffraction. The carbene complex is square-planar and the angle formed between the platinum square plane and the heterocyclic carbene ligand is 87.9(2)°. The C(1)-N(1) and C(1)-N(2) bond distances in the latter of 1.32(2) and 1.30(2) Å, respectively, are short for a single bond and indicate extensive π-bonding between the nitrogen atoms and the carbene carbon.  相似文献   

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