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1.
The reaction of compound Me2Si(NSiMe3)2Si(OH)Cl with Me2SiCl2 leads to the disiloxane Me2Si(NSiMe3)2Si(Cl)OSi(Me2)Cl (1). Hydrolysis of 1 in the presence of pyridine results in Me2Si(NSiMe3)2Si(OH)OSi(Me2)OH (2), which is allowed to react with SiCl4 to give cyclotrisiloxane [Me2Si(NSiMe3)2Si](OSiMe2)(OSiCl2)O (3). The treatment of 1 with (t-BuO)2Si(OH)2 forms cyclotrisiloxane [Me2Si(NSiMe3)2Si](OSiMe2)[OSi(Ot-Bu)2]O (4). Compound 3 is obtained as a crystalline solid while 4 is an oily liquid. The ring size of these new types of cyclotrisiloxanes with three different R2Si-units is confirmed by cryoscopy in benzene, 29Si NMR chemical shifts and in case of 3, additionally by a single X-ray diffraction study. The different electronegativities of the substituents in the R2Si-units lead to different bond lengths and bond angles within the Si3O3 cycle, which are discussed in detail in the molecular structure of 3.  相似文献   

2.
Metallation of (HMe2Si)(Me3Si)2CH (1) by LiMe gave the organolithium compound Li(THF)2C(SiMe3)2(SiMe2H) (2a), which exists in toluene solution as a mixture of covalent species and ion pairs [Li(THF)4][Li{C(SiMe3)2(SiMe2H)}2] (2b). Treatment of a mixture of 1 and LiMe with KOBut gave KC(SiMe3)2(SiMe2H) (3). This reacted with AlMe2Cl in hexane/THF to give Al(THF)Me2{C(SiMe3)2(Si Me2H)} (4). Treatment of (HMe2Si)(PhMe2Si)2CH (5) with LiMe in Et2O/THF gave the THF adduct [Li(THF)2C(SiMe2Ph)2(SiMe2H)] (6); in the presence of KOBut the solvent-free [K][C(SiMe2Ph)2(SiMe2H)] (7) was obtained. Crystal structure determinations showed that 6 crystallizes in a molecular lattice and 7 in an ionic lattice in which the coordination sphere of the potassium comprises phenyl groups and hydrogen atoms attached to silicon, as well as the central carbon of the bulky carbanion. Compound 7 reacted with an excess of AlMe2Cl to give [AlClMe{C(SiMe2Ph)2(SiMe2H)}]2 (8) and AlMe3. A small amount of the methoxo derivative [Al(OMe)Me{C(SiMe2Ph)2(SiMe2H)}]2 (9) was obtained as a byproduct, presumably after the accidental admission of traces of air. X-ray structural determinations showed that 8 forms halogen-bridged dimers, with the bulky ligands in the anti-configuration, and 9 forms methoxo-bridged species in which the bulky ligands are syn.  相似文献   

3.
The solid-state thermolysis (420–450 °С) of the new heterometallic coordination polymer [Li2Co2(Piv)6(μ-L)2]n (1, Piv is the anion of pivalic acid, L is 2-amino-5-methylpyridine) followed by annealing of the decomposition products at 500 °С was shown to afford LiCoO2 in quantitative yield. Compound 1 was characterized by X-ray diffraction and magnetic measurements.  相似文献   

4.
Treatment of LiC(SiMe2H)3]·2THF (1) with alkeny1chlorosilanes produced sterically hindered alkenylsilanes (410) of structure H2C=CH---(CH2)nSiRR′C(SiMe2H)3 (R=Me; R′=Me or Cl; n=0, 1, or 4). The Peterson reaction of 1 with carbonyl compounds gave sterically hindered olefins R(R′)C=C(SiMe2H)2. Pt or Rh catalyzed intramolecular hydrosilylation of H2C=CHSiMe2C(SiMe2H)3 (4) occurred to produce a new 1,3-disilacyclobutane derivative 15. Intermolecular hydrosilylation was favored for 5, 8, and 10, producing oligomeric products.  相似文献   

5.
Five crystalline 2-(dimethylsila)pyrimidine derivatives (Z) have been prepared in excellent 14 or satisfactory 5 yield and characterised. The source of each was ultimately Li[CH(SiMe2R)(SiMe2OMe)] [R = Me (B) or OMe (I)]. Compound 1 (Z with Ar = Ph, X = SiMe3, n = 1) was obtained from Z [with Ar = Ph, X = Li(OEt2), n = 4; previously isolated from B [P.B. Hitchcock, M.F. Lappert, X.-H. Wei, J. Organomet. Chem. 689 (2004) 1342]] and Me3SiCl. The potassium salt 2 [Z with Ar = C6H4But-4; X = K(thf)3, n = 2] was made from K[CH(SiMe3)(SiMe2OMe)] (C) (via B) and 4-ButC6H4CN. Treatment of 2 with 1,2-dibromoethane afforded 3 (Z with Ar = 4-ButC6H4; X = H, n = 1); which when reacted with successively n-butyllithium and Me3SiCl produced 4 (Z with Ar = 4-ButC6H4, X = SiMe3, n = 1). Compound 5 [Z with Ar = 4-ButC6H4, X = Li(hmpa)2, n = 1] resulted from I with 4-ButC6H4CN and then OP(NMe2)3 (≡ hmpa). Plausible reaction pathways from the appropriate alkali metal alkyl C or I to 2 or 5, respectively, are suggested; these involve regiospecific 1,3-migrations of SiMe2OMe from C → N and electrocyclic loss of Me3SiOMe or SiMe2(OMe)2, respectively. The X-ray structures of crystalline 1, 2 and 5 are presented.  相似文献   

6.
Three new tetrahedral rhenium cluster compounds [Re4Se4(PMe2Ph)4Br8]·1.5CH2Cl2 (1), [Re4Te4(PMe2Ph)4Br8]·CH2Cl2 (2), and [Re4Te4(PMe2Ph)4Cl8]·CH2Cl2 (3) have been synthesized by the reaction of the corresponding precursor chalcohalide complexes [Re4Q4(TeX2)4X8] (X = Br, Q = Se (for 1), Te (for 2); X = Cl, Q = Te (for 3)) with dimethylphenylphosphine in CH2Cl2. All compounds have been characterized by X-ray single-crystal diffraction and elemental analyses, IR and 31P NMR spectroscopy. 31P NMR spectroscopy indicates the formation of isomers in solution, confirmed by single-crystal X-ray analysis.  相似文献   

7.
The C,N-(trimethylsilyliminodiphenylphosphoranyl)silylmethylmetal complexes [Fe(L)2] (3), [Co(L)2] (4), [ZrCl3(L)]·0.83CH2Cl2 (5), [Fe(L)3] (6), [Fe(L′)2] (7) and [Co(L′)2] (8) have been prepared from the lithium compound Li[CH(SiMe2R)P(Ph)2NSiMe3] [1a, (R = Me) {≡ Li(L)}; 1b, (R = NEt2) {≡ Li(L′)}] and the appropriate metal chloride (or for 7, FeCl3). From Li[N(SiMe3)C(Ph)C(H)P(Ph)2NSiMe3] [≡ Li(L″)] (2), prepared in situ from Li(L) (1a) and PhCN, and CoCl2 there was obtained bis(3-trimethylsilylimino- diphenylphosphoranyl-2-phenyl-N-trimethylsilyl-1-azaallyl-N,N)cobalt(II) (9). These crystalline complexes 3-9 were characterised by their mass spectra, microanalyses, high spin magnetic moments (not 5) and for 5 multinuclear NMR solution spectra. The X-ray structure of 3 showed it to be a pseudotetrahedral bis(chelate), the iron atom at the spiro junction.  相似文献   

8.
The ternary rare earth boride carbides R10B9C12 (R = La, Ce, Pr, Nd) were synthesized by reacting the elements at temperatures between 1470 and 1760 K. The crystal structures (Ce10B9C12 type) were determined from single crystal X-ray diffraction data. For Pr10B9C12 we found: space group P41212, Z = 4, a = 8.4365(3) Å, c = 25.468(1) Å (R1 = 0.023 (wR2 = 0.044) from 2315 reflections with Io > 2σ(Io)); for Nd10B9C12, a = 8.3834(3) Å, c = 25.352(1) Å (R1 = 0.021 (wR2 = 0.044) from 1847 reflections with Io > 2σ(Io)). The three-dimensional network of rare earth atoms resulting from a stacking of slightly corrugated square nets has its voids filled with B4C4 and B5C8 finite chains. The lattice parameters of the isostructural compounds, formed with La and Ce, were refined from powder X-ray diffraction data. Magnetic properties are reported for all compounds. La10B9C12 is a temperature independent paramagnet down to 6 K. The remaining compounds show a tendency of ferromagnetic ordering at T < 10 K at elevated external fields (induced ferromagnets). The electrical resistivity for Ce10B9C12 reveals a weak metal-like temperature dependence below room temperature. From heat capacity measurements it can be concluded that the magnetic order is rather a short range type ordering and field induced in the case of Ce10B9C12 and Pr10B9C12.  相似文献   

9.
Crystalline [Li{N(SiMe2OMe)C(tBu)C(H)(SiMe3)}]2 (5), [Li{N(SiMe2OMe)C(Ph)C(H)(SiMe3)}]2 (6), [C(C6H3Me2-2,5)C(H)(SiMe3)}(TMEDA)](7), [Li{N(SiMe(OMe)2)C(tBu)C(H)(SiMe3)}(THF)]2 (8), Li{N(SiMe(OMe)2)C(Ph)C(H)(SiMe3)}(TMEDA) (9) and [Li{N(SiMe2OMe)C(tBu)C(H)(SiMe2OMe)}]2 (10) were readily obtained at ambient temperature from (i) [Li{CH(SiMe3)(SiMe2OMe)}]8 (1) and an equivalent portion of RCN (R=tBu (5), Ph (6) or 2,5-Me2C6H3 (7)); (ii) [Li{CH(SiMe3)(SiMe(OMe)2)}] (2) and an equivalent portion of tBuCN (8) or PhCN (9); and (iii) [Li{CH(SiMe2OMe)2}] (3) and one equivalent of tBuCN (10). Reactions (i) and (ii) were regiospecific with SiMe3−n(OMe)n>SiMe3 in 1,3-migration from C (in 1 or 2)→N. The 1-azaallyl ligand was bound to the lithium atom as a terminally bound κ1-enamide (8 and 10), a bridging η3-1-azaallyl (6), or a bridging κ1-enamide (5). The stereochemistry about the CC bond was Z for 5, 8 and 10 and E for 7. X-ray data are provided for 5, 6, 7, 8 and 10 and multinuclear NMR spectra data in C6D6 or C6D5CD3 for each of 5-10.  相似文献   

10.
Synthesised by refluxing the amine adduct [Me3Al·(PhCH2)2NLi·HN(CH2Ph)2] in toluene/THF, the title compound has been structurally characterised by X-ray diffraction, and the methane elimination/amide insertion processes involved in its formation have been modelled theoretically through a series of ab initio MO calculations.  相似文献   

11.
tBu2P–PLi–PtBu2 · 2THF reacts with [(R3P)2MCl2] (M = Pt, Pd, Ni; R3P = Et3P, pTol3P, Ph2EtP, iPr3P) to yield isomers of [(1,2‐η‐tBu2P=P–PtBu2)M(PR3)Cl], in which the tBu2P–P–PtBu2 ligand adopts the arrangement of a side‐on bonded 1,1‐di‐tert‐butyl‐2‐(di‐tert‐butylphosphanyl)diphosphenium cation. tBu2P–PLi–P(NEt2)2 · 2THF reacts with [(R3P)2MCl2] but does not form complexes with a tBu2P–P–P(NEt2)2 moiety, however, splitting of a P–P(NEt2)2 bond of the parent triphosphane takes place.  相似文献   

12.
13.
Novel half-sandwich [C9H5(SiMe3)2]ZrCl3 (3) and sandwich [C9H5(SiMe3)2](C5Me4R)ZrCl2 (R = CH3 (1), CH2CH2NMe2 (2)) complexes were prepared and characterized. The reduction of 2 by Mg in THF lead to (η5-C9H5(SiMe3)2)[η52(C,N)-C5Me4CH2CH2N(Me)CH2]ZrH (7). The structure of 7 was proved by NMR spectroscopy data. Hydrolysis of 2 resulted in the binuclear complex ([C5Me4CH2CH2NMe2]ZrCl2)2O (6). The crystal structures of 1 and 6 were established by X-ray diffraction analysis.  相似文献   

14.
The novel germanium-containing alkylidene complexes of molybdenum R3Ge-CHMo(NAr)(OCMe2CF3)2 (Ar = 2,6-i-Pr2C6H3; R = Me, Ph) have been prepared by the reaction of organogermanium vinyl reagents R3 GeCHCH2 with known alkylidene compounds Alkyl-CHMo(NAr)(OCMe2CF3)2 (Alkyl = But, PhMe2C). The titled compounds were isolated as crystalline solids and characterized by elemental analysis, 1H NMR, 13C NMR spectroscopy and X-ray diffraction studies. The geometry of the Mo atoms in the compounds can be described as a distorted tetrahedron.  相似文献   

15.
The results of simple microwave-assisted ligand substitution reactions of Os3(CO)12 are reported. In a remarkably short period of time, the labile complex Os3(CO)11(NCMe) is prepared in high yield without the need for a decarbonylation reagent such as trimethylamine oxide. Microwave irradiation of Os3(CO)12 in a relatively small amount of acetonitrile is shown to be a useful first step in two-step, one-pot syntheses of the cluster complexes Os3(CO)11(py) and Os3(CO)11(PPh3).  相似文献   

16.
The reaction of mono- and disubstituted alkynes with CH2I2-R3Al (R = Me, Et, i-Bu) was studied. It was found that the reaction of alkynes with CH2I2 in the presence of Me3Al gives β-iodoethyl-substituted cyclopropanes. The use of Et3Al or i-Bu3Al affords exclusively cyclopropylic organoaluminum compounds.  相似文献   

17.
Five 12-MC-4 organotin(IV) metallacrowns(MCs) with the types of [12-MCRSn(IV)N(shi)-4] (R = Et (1), Bu (2), Ph (3); H3Shi = salicylhydroxamic acid) and [12-MCRSn(IV)N(Clshi)-4] (R = Et (4), Bu (5), H3Clshi = 5-chlorosalicylhydroxamic acid) have been synthesized and characterized by elemental analyses, IR and TGA. X-ray single-crystal diffraction analyses were also carried out and showed that all complexes 1-5 contain a neutral 12-membered metallacrown ring which is formed by the succession of four repeating units of -[Sn-N-O]-, indicating the substituents on the tin(IV) atom are uninfluential in coordination of organotin(IV) centers with hydroxamic acid. Fluorescence properties of complexes 1-5 have been investigated, where complex 3 displays strong fluorescence emissions in the blue region. In addition, antitumor activities of complexes 4 and 5 have also been tested, and both the complexes exhibit weak activity towards human hepatocellular carcinoma cell line (Bel-7402) and Hela cell line.  相似文献   

18.
The chemistry of η3-allyl palladium complexes of the diphosphazane ligands, X2PN(Me)PX2 [X = OC6H5 (1) or OC6H3Me2-2,6 (2)] has been investigated.The reactions of the phenoxy derivative, (PhO)2PN(Me)P(OPh)2 with [Pd(η3-1,3-R′,R″-C3H3)(μ-Cl)]2 (R′ = R″ = H or Me; R′ = H, R″ = Me) give exclusively the palladium dimer, [Pd2{μ-(PhO)2PN(Me)P(OPh)2}2Cl2] (3); however, the analogous reaction with [Pd(η3-1,3-R′,R″-C3H3)(μ-Cl)]2 (R′ = R″ = Ph) gives the palladium dimer and the allyl palladium complex [Pd(η3-1,3-R′,R″-C3H3)(1)](PF6) (R′ = R″ = Ph) (4). On the other hand, the 2,6-dimethylphenoxy substituted derivative 2 reacts with (allyl) palladium chloro dimers to give stable allyl palladium complexes, [Pd(η3-1,3-R′,R″-C3H3)(2)](PF6) [R′ = R″ = H (5), Me (7) or Ph (8); R′ = H, R″ = Me (6)].Detailed NMR studies reveal that the complexes 6 and 7 exist as a mixture of isomers in solution; the relatively less favourable isomer, anti-[Pd(η3-1-Me-C3H4)(2)](PF6) (6b) and syn/anti-[Pd(η3-1,3-Me2-C3H3)(2)](PF6) (7b) are present to the extent of 25% and 40%, respectively. This result can be explained on the basis of the steric congestion around the donor phosphorus atoms in 2. The structures of four complexes (4, 5, 7a and 8) have been determined by X-ray crystallography; only one isomer is observed in the solid state in each case.  相似文献   

19.
Reactions of 1,4-dibromo-2,5-difluorobenzene with two equivalents of lithium diisopropylamide at low temperature (T < −90 °C) followed by a quench with a slight excess of ClPPh2 afford 1,4-dibromo-2,5-bis(diphenylphosphino)-3,6-difluorobenzene (1) in good yields. Reacting 1 with two equivalents of BuLi followed by a quench with a slight excess of ClPR2 yield novel 1,2,4,5-tetrakis(phosphino)-3,6-difluorobenzenes 1,4-(PPh2)2-2,5-(PR2)2-C6F2 (R = Ph (2a); R = iPr (2b); R = Et (2c)) in moderate yields. Compounds 1 and 2a-c were characterized by multinuclear NMR spectroscopy and elemental analyses. In addition, molecular structures of 2a-c have been determined by single crystal X-ray crystallography. Phosphorus atoms of PPh2/PR2 substituents in 2a-c are displaced from the plane of the central phenyl ring due to steric interactions with neighboring groups.  相似文献   

20.
Oxidative addition of methyl iodide to platinum (II) compounds [PtMe2{(Me2NCH2CH2NCH)Ar}] (Ar = phenanthryl or anthryl) produced the corresponding platinum (IV) compounds. Processes aimed at reducing the steric crowding at the coordination sphere of the platinum (IV) centre such as C-C restricted rotation of the pendant part of the ligand leading to rotamers and isomerisation of the CN moiety have been detected in solution. The obtained platinum (IV) compounds were characterised by elemental analyses, mass spectrometry and NMR spectroscopy. According to the crystallographic characterisation, the anthracene derivative gave an E conformer while a Z conformation was obtained for the phenanthrene derivative. In order to rationalize the experimental results, DFT calculations have been performed.  相似文献   

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