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1.
The potassium iminophosphanide complex [K 4(thf) 3(Me 3SiNPEt 2) 2(OSiMe 2OSiMe 2O)] 2 has been obtained by a melt reaction of Me 3SiNPEt 3 with potassium hydride at 140 °C in the presence of silicon grease (—OSiMe 2—) n and subsequent crystallization from thf solution. The colourless moisture sensitive single crystals are characterized by X‐ray diffraction: Space group P1¯, Z = 1, lattice dimensions at —70 °C: a = 1135.9(3), b = 1250.0(3), c = 1866.1(4) pm, α = 92.65(1)°, β = 100.80(1)°, γ = 93.57(1)°, R 1 = 0.0604. The centrosymmetric dimeric cluster aggregate is formed by two of the eight potassium ions which are connected with the central oxygen atom of both the (OSiMe 2OSiMe 2O) 2— chains as well as with one of their terminal O atoms each. The remaining potassium ions are connected with the phosphorus atoms of the iminophosphanide groups (Me 3SiNPEt 2) — as well as with its nitrogen atoms. They are terminally solvated by thf molecules. 相似文献
2.
The reaction of [(MenacnacDipp)Mn(μ-Cl)]2(2) (MenacnacDipp = HC(C(Me)NDipp)2; Dipp = 2,6-Pri2C6H3) with sodium triethylborohydride in a toluene—THF mixture afforded the complex [(MenacnacDipp)Mn(μ-H)2BEt2(THF)] (3). The reaction of 2 with Na[HBEt3] in toluene under THF-free conditions gave a mixture of products. The set and the ratio of these products in the resulting crystalline mixture were established by quantitative powder X-ray diffraction analysis: [(MenacnacDipp)Mn(μ-H)]2(1), [(MenacnacDipp)?Mn(μ-H)2BEt2] (4), and unreacted compound 2 in the ratio of 15:4:1 and traces of an unknown crystalline phase. The reaction of [(MenacnacDipp)VCl2] (5) with Na[HBEt3] yielded the compound [(MenacnacDipp)V(μ-H)(μ,κ1:1?C:C′?C2H4)BEt2] (6) containing the unusual ligand [HBEt2(CH2CH2)]2?. The vanadium analog of compound 3, [(MenacnacDipp)V(μ-H)2BEt2(THF)] (7), was isolated in one experiment. Besides. a small amount of the complex [(MenacnacDipp)V(μ-H)BEt3(THF)] (8) was detected in the mixture of crystalline products. The structures of compounds 3, 4, 6, 7, and 8 were determined by single-crystal X-ray diffraction. 相似文献
3.
Methyl(vinyl)dichlorosilane reacts with DMSO in the presence of hexamethyldisiloxane to give the corresponding linear oligosiloxanes
of the general formula Me 3Si(OSiMeVin)
n
OSiMe 3 ( n=1–6) as well as MeSi(OSiMe 3) 3 and Me 3Si(MeOSiVin)
m
OSi(OSiMe 3)(Me)OSiMe 3 ( m=1–2). The same reaction in the presence of chlorotrimethylsilane results in oligomers of the general formula Me 3Si(OSiMeVin)
n
Cl ( n=1–3). A possible scheme of their formation is discussed.
Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1614–1616, August, 1998. 相似文献
4.
Co II and Co III complexes containing nitrite and tridentate aromatic amine compounds [bis(6-methyl-2-pyridylmethyl)amine (Me 2bpa) and bis(2-pyridylmethyl)amine (bpa)] have been prepared as models of the catalytic center in Co-substituted nitrite reductase: [Co II(Me 2bpa)(NO 2)Cl] 2 · acetone ( 2), Co II(Me 2bpa)(NO 2) 2 ( 3), Co II(bpa)(NO 2)Cl ( 4), Co II(bpa)(NO 2) 2 ( 5), Co III(Me 2bpa)(NO 2)(CO 3) ( 6), and Co III(bpa)(NO 2) 3 ( 7). The X-ray crystal structure analyses of these Co II and Co III complexes indicated that the geometries of the cobalt centers are distorted octahedral and the Me 2bpa and bpa with three nitrogen donors exhibit mer- ( 2, 3, and 7) and fac-form ( 4 and 6). The coordination mode of nitrite depends on the cobalt oxidation state, to Co II through the oxygen (nitrito coordination, O- and O, O-coordination) and to Co III through nitrogen (nitro coordination, N-coordination mode). These findings are consistent with the results of their IR spectra, except that another oxygen of the O-coordinated nitrito group in 3 might interact weakly with Co II according to its IR spectrum. Reductions of the nitrite in 2, 3, 4, and 5 to nitrogen monoxide were not accelerated in the presence of proton, perhaps due to the nitrito coordination in these Co II complexes. 相似文献
5.
Self-assembly of 4,4′-bipyridine (bpy) with arene-ruthenium building blocks and 2,2′-bisbenzimidazole (H 2BiBzIm) in the presence of AgOTf (OTf = OSO 2CF 3) afforded tetranuclear cations of the type [Ru 4( η6-arene) 4(bpy) 2(BiBzIm) 2] 4+ (arene = p- iPrC 6H 4Me 1, C 6Me 6 2), while similar reactions by use of [( η6-C 6Me 6)Ru( μ-Cl)Cl] 2 and excess AgOTf led to isolation of a cationic coordination network {[Ru 4( η6-C 6Me 6) 4(bpy) 2(BiBzIm) 2·Ag 2(OTf) 4] 2+} n ( 3), which could also be obtained by treatment of [ 2] [OTf ]4 with AgOTf in methanol. Complex 3 is constructed by π coordination of BiBzIm( η2-carcon) with Ag(I). The coordination geometry around the silver(I) ion is pseudo-tetrahedral (taking the C=C group as one ligand). Self-assembly of only two components: [( η6-C 6Me 6)Ru( μ-Cl)Cl] 2 reacted with the 3-pyridyl-bian ( mPy-bian) linker in the presence of limited AgOTf to give a chloro-bridged metalla-rectangle [Ru 4( η6-C 6Me 6) 4( μ-Cl) 4( mPy-bian) 2Ag] 5+ ( 4), which enclosed a silver in the center. The coordination geometry around silver(I) in 4 is unusual square planar. The molecular structures of 1–4 were confirmed by X-ray crystallography along with other spectroscopic properties. 相似文献
6.
Abstract The reactions of a variety of electrophiles with the N-silyl-P-trifluoroethoxyphosphoranimine anion Me 3Sin°P(Me)(OCH 2CF 3)CH ? 2 ( 1a), prepared by the deprotonation of the dimethyl precursor Me 3SiN[dbnd]P(OCH 2CF 3)Me 2 ( 1) with n-BuLi in Et 2O at-78°C, were studied. Thus, treatment of 1a with alkyl halides, ethyl chloroformate, or bromine afforded the new N-silylphosphoranimine derivatives Me 3SiN[dbnd]P(Me)(OCH 2CF 3)CH 2R [ 2: R = Me, 3: R = CH 2Ph, 4: R = CH[sbnd]CH 2, 5: R = C(O)OEt, and 6: R = Br]. In another series, when 1a was allowed to react with various carbonyl compounds, 1,2-addition of the anion to the carbonyl group was observed. Quenching with Me 3SiCl gave the O-silylated products Me 3SiN[dbnd]P(Me)(OCH 2CF 3)CH 2°C(OSiMe 3)R 1R 2 [ 7: R 1 = R 2 = Me; 8: R 1 = Me, R 2 = Ph; 9: R 1 = Me, R 2 = CH[sbnd]CH 2; and 10: R 1 = H, R 2 = Ph]. Compounds 2–10 were obtained as distillable, thermally stable liquids and were characterized by NMR spectroscopy ( 1H, 13C, and 31P) and elemental analysis. 相似文献
7.
On Reactions of Hexachlorodiberyllate with Trimethylsilyl‐ N‐dimethylamide. Crystal Structures of (Ph 4P) 3[Be 2Cl 5(OSiMe 3)][BeCl 3(Me 2NSiMe 3)], (Ph 4P)[BeCl 3(HNMe 2)], and (Ph 4P)(H 2NMe 2)[BeCl 4] Reactions of bis‐tetraphenylphosphonium hexachlorodiberyllate, (Ph 4P) 2[Be 2Cl 6], with trimethylsilyl‐ N‐dimethylamide under different conditions lead to the novel chloroberyllate derivatives (Ph 4P) 3[Be 2Cl 5(OSiMe 3)][BeCl 3(Me 2NSiMe 3)] ( 1 ), (Ph 4P)[BeCl 3(HNMe 2)] ( 2 ), and (Ph 4P)(H 2NMe 2)[BeCl 4] ( 3 ). 1 ‐ 3 were characterized by IR spectroscopy and crystal structure determinations. 1· 4CH 2Cl 2: Space group P1¯, Z = 2, lattice dimensions at 193 K: a = 1115.6(1), b = 2110.7(2), c = 2145.0(3) pm, α = 71.38(1)°, β = 85.66(1)°, γ = 85.24(1)°, R 1 = 0.0732. The [Be 2Cl 5(OSiMe 3)] 2— ion in the structure of 1 is derived from the [Be 2Cl 6] 2— ion by substitution of a μ‐Cl ligand by the oxygen atom of the (OSiMe 3) — group. The second anion, [BeCl 3(Me 2NSiMe 3)] —, can be described as donor acceptor complex with a short Be—N bond of 179(1) pm. 2 : Space group P1¯, Z = 2, lattice dimensions at 193 K: a = 1063.1(1), b = 1072.0(1), c = 1238.3(1) pm, α = 87.55(1)°, β = 74.86(1)°, γ = 69.73(1)°, R 1 = 0.0299. The anion of 2 forms a centrosymmetric dimer [BeCl 3(HNMe 2)] 22— via N—H···Cl bridges of the two donor acceptor complex units with Be—N separations of 175.2(2) pm. 3 : Space group Pbca, Z = 8, lattice dimensions at 193 K: a = 926.9(1), b = 2164.7(1), c = 2732.7(1) pm, R 1 = 0.0495. The structure of 3 contains centrosymmetric ion quadrupoles [(Me 2NH 2)(BeCl 4)] 22— forming by N—H···Cl bridges between (Me 2NH 2) + and [BeCl 4] 2— ions. 相似文献
8.
Abstract Tris-(trimethylsilyl)phosphane and their organo substituted derivatives (Me 3Si) 3?nP(Me 3C) n (n: 0, 1, 2) ( la-c) had been found suitable for the insertion of selenium into the phosphorus-silicon bond. At deep temperatures all silylselenophosphanes of the series (Me 3SiSe) 3?nP(Me 3C n) ( 2a-c) are formed in a nearly quantitative reaction, if no excess selenium is present. (Me 3C)(Me 3SiSe) 2P=Se ( 3b) and (Me 3C) 2(Me 3SiSe)P=Se ( 3c) are detectable in small quantities as the only by-products of the reaction of ( Ib-c), whereas ( la) end in the formation of ( 2a) and traces of the dimer (Me 3SiSe) 2P-P(SeSiMe 3) 2 ( 4). On exposure to light or at elevated temperatures ( 2a) undergoes a disproportionation, forming Se=P(SeSiMe 3) 3 ( 3a), and the heterocycles P 3Se 4(SeSiMe 3) ( 5) and α-P 4Se 3(SeSiMe 3) 2 ( 6). (Me 3Si) 2Se is spUt off as a condensation product. After further irradiation or prolonged standing at room temperature, an insoluble oligomer is formed. The constitutions of ( 2-6) were determined by the analysis of their 31P- and 77Se-nmr spectra. 相似文献
9.
Transition Metal-substituted Acylphosphanes and Phosphaalkenes. 22. Insertions of Hexafluoroacetone into the PX-Bond of Metallophosphanes (η 5-C 5Me 5)(CO) 2M? PX 2 (M = Fe, Ru; X = Me 3Si, Cl). Structure Determination of (η 5-C 5Me 5)(CO) 2Fe? P(SiMe 3)C(CF 3) 2(OSiMe 3) Reaction of the metallophosphanes (η 5-C 5Me 5)(CO) 2M? P(SiMe 3) 2 ( 1a : M = Fe; 1b : M = Ru) with hexafluoroacetone (HFA) afforded the complexes (η 5-C 5Me 5)(CO) 2M? P(SiMe 3)C(CF 3) 2(OSiMe 3) ( 2a, b ). The attempted synthesis of a metallophosphaalkene from 2a by thermal elimination of hexamethyldisiloxane failed. The acid catalyzed hydrolysis of 2a afforded compound (η 5-C 5Me 5) · (CO) 2Fe? P(H)C(CF 3) 2(OSiMe 3) ( 3 ). Hexafluoracetone and (η 5-C 5Me 5)(CO) 2Fe? PCl 2 ( 4 ) under-went reaction to give the metallochlorophosphan (η 5-C 5Me 5) · (CO) 2Fe? P(Cl)? O? C(CF 3) 2Cl ( 5 ). Constitutions and configurations of the compounds ( 2–5 ) were established by elemental analyses and spectroscopic data (IR, 1H-, 13C, 19F-, 29Si-, 31P-NMR, MS). The molecular structure of 2a was determined by x-ray diffraction analysis. 相似文献
10.
Reaction of the [Rh(η 5-C 5Me 5)(NCMe) 3] 2+ ( 1) dication with the hexaosmium [Os 6(CO) 17] 2− ( 2) dianion leads to the initial formation of [Os 6(CO) 17Rh(η 5-C 5Me 5)] ( 3). This cluster readily adds CO to form [Os 6(CO) 18Rh(η 5-C 5Me 5)] ( 4) which has been characterised crystallographically. 3 also adds dihydrogen to give [Os 6H 2(CO) 17Rh(η 5-C 5Me 5)] ( 5) and undergoes a substitution reaction with PPh 3 to form [Os 6(CO) 16(PPh 3)Rh(η 5-C 5Me 5)] ( 6). With the [Ru 6(CO) 18] 2− ( 7) dianion, [Rh(η 5-C 5Me 5)(NCMe) 3] 2+ ( 1) reacts to form three mixed-metal clusters [Ru 5(CO) 15Rh(η 5-C 5Me 5)] ( 8), [Ru 6(CO) 18Rh(η 5-C 5Me 5)] ( 9) and [Ru 6(CO) 18Rh 2(η 5-C 5Me 5) 2] ( 10). The clusters have been characterised spectroscopically and the structures of 8 and 10 have been confirmed crystallographically. The cluster 8 undergoes a substitution reaction with P(OMe) 3 to form the disubstituted product [Ru 5(CO) 13(P(OMe) 3) 2Rh((η 5-C 5Me 5)] ( 11) which has also been characterised crystallographically. 相似文献
11.
Abstract The UV irradiation of (η 5-C 5Me 5)Re(CO) 3 in the presence of 1,2,4,5-C 6Cl 4H 2 and 1,3,5-C 6Cl 3H 3 (λ = 350 nm, hexane solution) effected intramolecular C—Cl activation, generating the complexes trans-(η 5-C 5Me 5)Re(CO) 2(2,4,5-C 6Cl 5-nH n)Cl, (( 1), n = 2; ( 2), n = 3), respectively. Complex ( 1) dissolved in polar organic solvents produces, an equilibrium mixture with its cis isomer. The reaction of ( 1) with AgBF 4, in acetonitrile, led to formation of the cationic complex [ cis-(η 5-C 5Me 5)Re(CO) 2(2,4,5-C 6Cl 3H 2)(MeCN)] +. The tetramethylfulvene complex (η 6-C 5Me 4CH 2)Re(CO) 2(2,4,5-C 6Cl 3H 2) ( 3) was obtained by reacting the cationic complex with the fluorinating agent Et 3N′3HF. 相似文献
12.
Summary. The reaction of Ru Tp( COD)Cl ( 1) with P Ph2Pri and terminal alkynes HCC R ( R=C 6H 5, C 4H 3S, C 6H 4O Me, Fc, C 6H 4– Fc, C 6H 9) affords the neutral vinylidene complexes Ru Tp(P Ph2Pri) (Cl)(=C=CH R) ( 2a– 2f) in high yields. These complexes do not react with MeOH to give methoxy carbene complexes of the type Ru Tp(P Ph2Pri)(Cl)(=C(O Me)CH 2R), but react with oxygen to yield the CO complex Ru Tp(P Ph2R)(Cl)(CO) ( 3). The structures of 2b, 2f, and 3 have been determined by X-ray crystallography. 相似文献
13.
Me 3NO activation of the methylidyne-bridged cluster HRu 3(CO) 10(μ-COMe) ( 1) in the presence of the unsaturated diphosphine ligand 2,3-bis(diphenylphosphino)maleic anhydride (bma) furnishes the bma-substituted cluster HRu 3(CO) 8(bma)(μ-COMe) ( 2) and the diphenylphosphine-substituted cluster HRu 3(CO) 8(Ph 2PH)[μ-PPh 2C=CC(O)OC(O)] ( 3) as the major and minor products, respectively. The 1H and 31P NMR data indicate that the bma ligand in cluster 2 is chelated to one of the ruthenium atoms that is bridged by the hydride and methylidyne ligands. Cluster 3 has been fully characterized in solution by IR and NMR spectroscopies, and the solid-state structure determined by X-ray crystallography. 3 crystallizes in the monoclinic space P2 1, a?=?12.1467(7)?Å, b?=?19.284(1)?Å, c?=?16.867(1)?Å, β?=?109.639(6)°, V?=?3721.0(4)?Å 3, Z?=?4, and d calcd?=?1.774?g?cm ?3; R?=?0.0325, R w?=?0.0383 for 3518 reflections with I?>?3σ( I). The X-ray data confirm that one of the P–C(maleic anhydride) bonds of the bma ligand has been cleaved and that cluster 3 contains Ph 2PH and μ-PPh 2C=CC(O)OC(O) ligands, the latter which functions as a face-capping ligand to all three ruthenium atoms. Control experiments indicate that cluster 2 does not function as a precursor to cluster 3 under the employed reaction conditions. 相似文献
14.
The reaction of Ru Tp( COD)Cl ( 1) with P Ph2Pri and terminal alkynes HCC R ( R=C 6H 5, C 4H 3S, C 6H 4O Me, Fc, C 6H 4– Fc, C 6H 9) affords the neutral vinylidene complexes Ru Tp(P Ph2Pri) (Cl)(=C=CH R) ( 2a– 2f) in high yields. These complexes do not react with MeOH to give methoxy carbene complexes of the type Ru Tp(P Ph2Pri)(Cl)(=C(O Me)CH 2R), but react with oxygen to yield the CO complex Ru Tp(P Ph2R)(Cl)(CO) ( 3). The structures of 2b, 2f, and 3 have been determined by X-ray crystallography. 相似文献
15.
Crystallization of [Cu( β-diketonate)(PPh 3) 2] ( 1a, β-diketonate=1-ferrocenyl-butane-1,3-dionato (= fb); 1b,?=?1,3-diferrocenyl-propane-1,3-dionato (= dfp)) from ethanol, layered with a mixture of pentane/diethyl ether of ratio 1?:?1 (v/v) in air, afforded Cu(II)-oxo clusters [Cu 10( fb) 8(O) 4( tmdd) 2]·1.5Et 2O ( 2) and [Cu 7( dfp) 6(O) 2(OH) 2( tmdd)]·2Et 2O ( 3), respectively, in minor yield ( tmdd?=?1 κ 2 C,3 κ 2 C-tetramethyldisiloxane-1,3-diolato). These clusters were obtained in somewhat better yield when HOSiMe 2OSiMe 2OH was added to the crystallization mixtures. The molecular structures of 2 and 3 in the solid state are reported. 相似文献
16.
The mono(pentamethylcyclopentadienyl) lanthanide complexes [(C 5Me 5)Yb( μ-I)( μ- η 5?: η 5-C 5Me 5)Yb(C 5Me 5)] n ( 1), {[(C 5Me 5)Sm] 3( μ-Cl) 4( μ 3-Cl)( μ 3-OH)(THF)} 2 ( 2), {[(C 5Me 5)Sm] 2 ( μ-OH)( μ-Cl) 4( μ 3-Cl)Mg(THF) 2} 2 ( 3), [(C 5Me 5) 2Sm]( μ-Cl) 6( μ 3-Cl) 2( μ 4-Cl)[(C 5Me 5)Sm] 4 ( 4), {[(C 5Me 5)Nd] 3( μ 3-Cl) 4( μ 4-Cl) 2( μ 3-O 2CPh) 2K 2( η 6-C 7H 8)} 2 ( 5), [(C 5Me 5)Nd(C 8H 8)] 2( μ-dioxane) ( 6), [(C 5Me 5)Yb(MeO tBu)] 2( μ- η 8?:? η 8-C 8H 8) ( 7), [(C 5Me 5)Dy( μ-I) 2] 3 ( 8), and [(C 5Me 5) Tm(MeCN) 6]I 2 ( 9), have been identified by X-ray crystallography. 1 is unusual in that it has a μ- η 5?:? η 5-C 5Me 5 ring that generates a local bent metallocene environment around ytterbium. Complexes 2– 5 demonstrate the versatility of bridging chlorides in generating a variety of structures for mono(pentamethylcyclopentadienyl) lanthanide halides. Complex 6 shows how dioxane can generate a crystallographically-analyzable complex by bridging two mixed-ligand metallocene units that do not readily crystallize with THF. The structure of 7 shows how methyl tert-butyl ether (MTBE) ligates a lanthanide. Complex 8 is a trimeric cyclopentadienyl lanthanide halide unusual in that it has six bridging halides that roughly define a trigonal prism. Complex 9 constitutes an organometallic example of a lanthanide in which acetonitrile completely displaces iodide counterions. 相似文献
17.
Eight new dicobalt-iron clusters have been synthesised and structurally characterized. Treatment of ( μ3-S)FeCo 2(CO) 9 ( A) with monophosphane ligands tris(4-fluorophenyl)phosphane, tris(4-methoxyphenyl)phosphane, or tris(2-furyl)phosphane in the presence of Me 3NO?2H 2O afforded monosubstituted complexes ( μ3-S)FeCo 2(CO) 8L [L = P(4-C 6H 4F) 3, 1; P(4-C 6H 4OMe) 3, 3; P(2-C 4H 3O) 3, 5] and disubstituted complexes ( μ3-S)FeCo 2(CO) 7L 2 [L = P(4-C 6H 4F) 3, 2; P(4-C 6H 4OMe) 3, 4; P(2-C 4H 3O) 3, 6]. Reaction of complex A with Ph 2PN[CH(CH 3) 2]PPh 2 in refluxing toluene gave complex ( μ3-S)FeCo 2(CO) 7{Ph 2PN[CH(CH 3) 2]PPh 2} ( 7) with an intramolecular bridging diphosphane ligand. Reaction of complex A with trans-1,2-bis(diphenylphosphino)ethylene ( trans-dppv) and Me 3NO?2H 2O yielded complex [( μ3-S)FeCo 2(CO) 8] 2( trans-Ph 2PCH = CHPPh 2) ( 8) with an intermolecular bridging diphosphane ligand. The new complexes 1–8 were characterized by elemental analysis, IR, 1H NMR, 31P{ 1H} NMR, and 13C{ 1H} NMR spectroscopy, particularly for 1, 3, and 6– 8 by X-ray crystallography. 相似文献
18.
The interactions of potentially dinucleating bridging functionalities ( I–VI) with the ruthenium-bis(bypyridine) precursor [Ru II(bpy) 2(EtOH) 2] 2+have been explored. The bridging functions I, II and VI directly result in the expected dinuclear complexes of the type [(bpy) 2Ru IIL nRu II(bpy) 2] z+ ( 1, 2, 7 and 8) (n = 0, z =4 and n = -2, z = 2). The bridging ligand III undergoes N-N or N-C bond cleavage reaction on coordination to the Ru II(bpy) 2 core which eventually yields a mononuclear complex of the type [(bpy) 2Ru II(L)] +, 3, where L = -OC 6H 3(R)C(R′)=N-H. However, the electrogenerated mononuclear ruthenium(III) congener, 3 +in acetonitrile dimerises to [(bpy) 2Ru III { -OC 6H 3(R)C(R′)=N-N=(R′)C(R)C 6H 3O -}Ru III(bpy) 2] 4+ ( 4). In the presence of a slight amount of water content in the acetonitrile solvent the dimeric species ( 4) reduces back to the starting ruthenium( II) monomer ( 3). The preformed bridging ligand IV undergoes multiple transformations on coordination to the Ru(bpy) 2 core, such as hydrolysis of the imine groups of IV followed by intermolecular head-to-tail oxidative coupling of the resultant amino phenol moieties, which in turn results
in a new class of dimeric complex of the type [(bpy) 2Ru II
-OC 6H 4-N=C 6H 3(=NH)O -Ru II(bpy) 2] 2+ ( 5). In 5, the bridging ligand comprises of two N,O chelating binding sites each formally in the semiquinone level and there is a p-benzoquinonediimine bridge between the metal centres. In complex 6, the preformed bridging ligand, 3,6-bis(3,5-dimethylpyrazol-1-yl)-1,2-dihydro-1,2,4,5-tetrazine, H 2L ( V) undergoes oxidative dehydrogenation to aromatic tetrazine based bridging unit, 3,6-bis(3,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazine,
L. The detailed spectroelectrochemical aspects of the complexes have been studied in order to understand the role of the bridging
units towards the intermetallic electronic coupling in the dinuclear complexes. 相似文献
19.
The lithium silanolate LiOSiMe 3 is accessible from the reaction of Me 3SiOSiMe 3 with LiMe in tetrahydrofuran. Single crystals of [Li 7(OSiMe 3) 7(THF)] were obtained from toluene at 25 °C. The structure of [Li 7(OSiMe 3) 7(THF)] ( C2/ c) features a capped trigonal antiprismatic arrangement of seven Li atoms. The Li atoms in [Li 7(OSiMe 3) 7(THF)] are μ3‐bridged by seven O atoms of the silanolate ligand. 相似文献
20.
1-Trimethylsiloxyalkyl-bis(trimethylsilyl)silanes ( 5 ), obtained by a base induced isomerization of easily accessable 1-hydroxyalkyl-tris(trimethylsilyl)silanes ( 1 ) were hydrolized to give 1-hydroxyalkyl-bis(trimethylsilyl)silanes ( 6 ), which in presence of sodium hydride underwent a further 1,3-Si,O-trimethylsilyl migration resulting in the formation of 1-trimethylsiloxyalkyl-disilanes Me 3SiSiH 2–C(OSiMe 3)R 1R 2 ( 7 ). Under acidic conditions, the alkoxysilanes 5 isomerized in a Me 3Si/OSiMe 3 exchange under formation of the 1-trimethylsilylalkyldisiloxanes 10 , which were hydrolyzed affording the silanols 11 . Chlorination of the H-silanes 5 with CCl 4 gave the chlorosilanes 12 , which underwent rapid thermal isomerizations to give via the 1-chloroalkyldisiloxanes 13 the 1-trimethylsilylalkyl-chlorodisiloxanes 15 . Hydrolysis of 12 or 15 , resp., finally afforded the 1-trimethylsilylalkyl-silanediols 18 . Possible mechanisms of the various isomerization processes are discussed. The structures of the products described were elucidated by full spectral analyses. For 18 a the results of an X-ray structural analysis are given. 相似文献
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