On Chalcogenolates. 144. Synthesis and Properties of Alkali Metal t-Butyl Carbonates. Reinvestigations of Trimethylsilyl Carbonates The t-butyl carbonates M[O2C? OC(CH3)3], where M = Li, Na, K, Rb, Cs, have been prepared by reaction of the corresponding t-butoxide with CO2 and characterized by means of diverse methods. The equivalent conductivities of the [O2C? OC(CH3)3]? ion in aqueous solution have been determined and the Stokes radius, the radius of the hydrated ion, and the diffusion coefficient were calculated. The dissociation constant of t-butyl carbonic acid in water at 25°C is Ka = (1.63 ± 0.03)· 10?8. The thermodynamic data of dissociation were calculated. New data of trimethylsilyl carbonates [O2C? OSi(CH3)3]? are given. 相似文献
Reaction of [(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2 with Neopentyllithium: Formation of {[(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2CH2CMe3} ? [Li(TMEDA)2]⊕ The recently synthesized methylene bridged dialuminium compound [(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2 reacts with neopentyl lithium in the presence of TMEDA to give the stable {[(Me3Si)2CH]2Al? CH2? Al [CH(SiMe3)2]2CH2 · CMe3}? [Li(TMEDA)2]⊕ decomposing at 115°C. The aluminium atoms therein are not additionally bridged, but the new substituent is occupying a terminal position as detected by crystal structure determination. A compound is formed containing a saturated, fourfold coordinated neighbouring a formally unsaturated, threefold coordinated aluminium atom. Due to high sterical restrictions the Al? C bonds are lengthened up to 209.0(3) pm at the alanate site and the Al? C? Al angle in the methylene bridge is extraordinarily enlarged to 144.4(2)°. 相似文献
On Chalcogenolates. 96. Studies on Trimethylsilyl Carbonates of Alkali Metals The trimethylsilyl carbonates M[O2COSi(CH3)3] with M = Li, Na, K, Rb, Cs have been prepared by reaction of Co2 with the corresponding silanolate. Infrared spectra, electron absorption spectra, 1H-NMR spectra as well as mass spectra are communicated. In aqueous solution the equivalent conductivities of [O2COSi(CH3)3]? have been determined by means of conductivity measurements. The diffusion coefficient of the ion was calculated. The dissociation constant of trimethylsilyl carbonic acid in water at 20°C is Ka = (4,83 ± 0,5) · 10?10. The thermodynamic data of the dissociation were calculated. 相似文献
Solvent-free Synthesis of Tetramethylammonium Salts: Synthesis and Characterization of [N(CH3)4]2[C2O4], [N(CH3)4][CO3CH3], [N(CH3)4][NO2], [N(CH3)4][CO2H], and [N(CH3)4][O2C(CH2)2CO2CH3] A general procedure to synthesize tetramethylammonium salts is presented. Several tetramethylammonium salts were prepared in a crystalline state by solvent-free reaction of trimethylamine and different methyl compounds at mild conditions: [N(CH3)4]2[C2O4] (cubic; a = 1 114.8(3) pm), [N(CH3)4][CO3CH3] (P21/n; a = 813.64(3), b = 953.36(3), c = 1 131.3(4) pm, β = 90.03(1)°), [N(CH3)4][NO2] (Pmmn; a = 821.2(4), b = 746.5(3), c = 551.5(2) pm), [N(CH3)4][CO2H] (Pmmn; a = 792.8(7), b = 791.7(3), c = 563.3(4) pm) and [N(CH3)4][O2C(CH2)2CO2CH3] (P21; a = 731.1(2), b = 826.4(3), c = 1 025.2(3) pm, β = 110.1(1)°). The tetramethylammonium salts were characterized by IR-spectroscopy and X-ray diffraction. The crystal structures of the methylcarbonate and the nitrite are described. 相似文献
Structural Characterization of Bis(metallated) Derivatives of 3, 3‐Dimethyl‐1, 5‐bis(trimethylsilyl)‐1, 5‐diaza‐pentane with Lithium and Aluminum and of two Donor‐substituted Digallanes The diaminopropane derivative Me2C[CH2N(H)SiMe3]2 is metallated with n‐butyllithium and lithium tetrahydridoaluminate to obtain Me2C[CH2N(Li)SiMe3]2 and Me2C[CH2N(Li)SiMe3][CH2N(AlH2)SiMe3], respectively. Both compounds exhibit a central eight‐membered ring, Li4N4 or Li2Al2N4. Me2C[CH2N(Li)SiMe3]2 reacts with Ga2Cl4 · 2dioxane under formation of the corresponding tetra(amino)digallane. This is monomeric, in contrast to a dimeric tetraalkoxy‐substituted digallane, Ga4OtBu8. All compounds were characterized by single crystal X‐ray crystallography. 相似文献
The solid state chemistry of bis(trimethyltin) azide hydroxide and hexamethyl-1,5-diazidotristannoxane has been investigated by Mössbauer, infrared and Raman spectroscopy. The structure of [(CH3)3Sn]2(OH)N3 may be described as polymeric trigonal bipyramidal, in which (CH3)3SNIV moieties are bridged by OH and N3 (through α-nitrogen) groups, and the chains are cross-linked by hydrogen bonding between oxygens and the γ-nitrogens of the azide groups. The structure of the tristannoxane is assumed to be that of a dimeric oligomer [N3(CH3)2Sn[OSn(CH3)2]2N3]2 containing five-coordinated trigonal bipyramidal SnIV arising from cross-linking through the oxygens and the two α-bridging azides. 相似文献
[Cu4(NPMe3)3(O2C? CH3)5] – a Tetrameric Phosphorane Iminato Complex of Copper(II). Synthesis, Crystal Structure, Magnetic Behaviour, and EPR Spectrum The title compound and the corresponding benzoate complex [Cu4(NPMe3)3(O2C? C6H5)5] have been prepared by reactions of copper(II)acetate and copper(II)benzoate, respectively, with Me3SiNPMe3 in dichloromethane. Both complexes are characterized by IR spectroscopy. The acetate complex is additionally characterized by the measurement of the magnetic susceptibility, by its EPR spectrum, and by a crystal structure determination. [Cu4(NPMe3)3(O2C? CH3)5] · CH2Cl2: Space group I41/a, Z = 16, structure solution with 7 960 independent reflections, R = 0.044. Lattice dimensions at ?70°C: a = b = 3 670.6; c = 1 091.9 pm. The structure consists of four Cu atoms which are arranged at the corners of a distorted tetrahedron with Cu…?Cu distances between 290 and 318 pm. Three of the faces of the tetrahedron are linked by μ3-N atoms of the phosphorane iminato groups. Three of the acetate ligands form chelates, the other two are monofunctionally coordinated. Three of the copper atoms have a planar surrounding, the forth Cu atom has a (4 + 1) coordination. 相似文献
Enantiomerically pure triflones R1CH(R2)SO2CF3 have been synthesized starting from the corresponding chiral alcohols via thiols and trifluoromethylsulfanes. Key steps of the syntheses of the sulfanes are the photochemical trifluoromethylation of the thiols with CF3Hal (Hal=halide) or substitution of alkoxyphosphinediamines with CF3SSCF3. The deprotonation of RCH(Me)SO2CF3 (R=CH2Ph, iHex) with nBuLi with the formation of salts [RC(Me)? SO2CF3]Li and their electrophilic capture both occurred with high enantioselectivities. Displacement of the SO2CF3 group of (S)‐MeOCH2C(Me)(CH2Ph)SO2CF3 (95 % ee) by an ethyl group through the reaction with AlEt3 gave alkane MeOCH2C(Me)(CH2Ph)Et of 96 % ee. Racemization of salts [R1C(R2)SO2CF3]Li follows first‐order kinetics and is mainly an enthalpic process with small negative activation entropy as revealed by polarimetry and dynamic NMR (DNMR) spectroscopy. This is in accordance with a Cα? S bond rotation as the rate‐determining step. Lithium α‐(S)‐trifluoromethyl‐ and α‐(S)‐nonafluorobutylsulfonyl carbanion salts have a much higher racemization barrier than the corresponding α‐(S)‐tert‐butylsulfonyl carbanion salts. Whereas [PhCH2C(Me)SO2tBu]Li/DMPU (DMPU = dimethylpropylurea) has a half‐life of racemization at ?105 °C of 2.4 h, that of [PhCH2C(Me)SO2CF3]Li at ?78 °C is 30 d. DNMR spectroscopy of amides (PhCH2)2NSO2CF3 and (PhCH2)N(Ph)SO2CF3 gave N? S rotational barriers that seem to be distinctly higher than those of nonfluorinated sulfonamides. NMR spectroscopy of [PhCH2C(Ph)SO2R]M (M=Li, K, NBu4; R=CF3, tBu) shows for both salts a confinement of the negative charge mainly to the Cα atom and a significant benzylic stabilization that is weaker in the trifluoromethylsulfonyl carbanion. According to crystal structure analyses, the carbanions of salts {[PhCH2C(Ph)SO2CF3]Li? L }2 ( L =2 THF, tetramethylethylenediamine (TMEDA)) and [PhCH2C(Ph)SO2CF3]NBu4 have the typical chiral Cα? S conformation of α‐sulfonyl carbanions, planar Cα atoms, and short Cα? S bonds. Ab initio calculations of [MeC(Ph)SO2tBu]? and [MeC(Ph)SO2CF3]? showed for the fluorinated carbanion stronger nC→σ* and nO→σ* interactions and a weaker benzylic stabilization. According to natural bond orbital (NBO) calculations of [R1C(R2)SO2R]? (R=tBu, CF3) the nC→σ*S? R interaction is much stronger for R=CF3. Ab initio calculations gave for [MeC(Ph)SO2tBu]Li ? 2 Me2O an O,Li,Cα contact ion pair (CIP) and for [MeC(Ph)SO2CF3]Li ? 2 Me2O an O,Li,O CIP. According to cryoscopy, [PhCH2C(Ph)SO2CF3]Li, [iHexC(Me)SO2CF3]Li, and [PhCH2C(Ph)SO2CF3]NBu4 predominantly form monomers in tetrahydrofuran (THF) at ?108 °C. The NMR spectroscopic data of salts [R1(R2)SO2R3]Li (R3=tBu, CF3) indicate that the dominating monomeric CIPs are devoid of Cα? Li bonds. 相似文献
Abstract Cobalt(III) complexes of the type [Co(en)2(chel)]X.nH2O where en = ethylenediamine, chel = phthalato = C6H4CO2)2?2, maleato = (O2CCH = CHCO2)2?, succinato = (O2CCH2CH2CO2)2?, homophthalato = (O2CC6H4(CH2)CO2)2?, citraconato = (O2CC(CH3) = CHCO2)2?, itaconato = (CH2 = C(CO2)CH2CO2)2?, X = NO?3, Br?, (O2CC6H4CO2H)?, (O2CHC = CHCO2H)?, (O2C(CH2)2CO2H)?, (O2CC6H4(CH2)CO2H)?, (O2CHC = C(CH2)-CO2H)?, and (O2C-CH2?C(= CH2)-CO2H)?, [Co(en)2(malonato)]X.2H2O (where malonato = (O2CCH2CO2)2?, X = Cl?, Br?, and NO?3) and [Co(en)2CO3]Cl.2H2O have been investigated for their bacterial activity against Escherichia coli B growing on EMB agar and in minimal glucose media both in lag and log phases. Among the most active are where chel = phthalato and homophthalato. The effects are distinct from those known for compounds of Pt, e.g., cis?[Pt(NH3)2Cl2] and rhodium, e.g., trans?[Rh(C5H5N)4,Cl2].6H2O. Antagonisms are reported. 相似文献
The reactions of phosphonium‐substituted metallabenzenes and metallapyridinium with bis(diphenylphosphino)methane (DPPM) were investigated. Treatment of [Os{CHC(PPh3)CHC(PPh3)CH}Cl2(PPh3)2]Cl with DPPM produced osmabenzenes [Os{CHC(PPh3)CHC(PPh3)CH}Cl2{(PPh2)CH2(PPh2)}]Cl ( 2 ), [Os{CHC(PPh3)CHC(PPh3)CH}Cl{(PPh2)CH2(PPh2)}2]Cl2 ( 3 ), and cyclic osmium η2‐allene complex [Os{CH?C(PPh3)CH?(η2‐C?CH)}Cl2{(PPh2)CH2(PPh2)}2]Cl ( 4 ). When the analogue complex of osmabenzene 1 , ruthenabenzene [Ru{CHC(PPh3)CHC(PPh3)CH}Cl2(PPh3)2]Cl, was used, the reaction produced ruthenacyclohexadiene [Ru{CH?C(PPh3)CH?C(PPh3)CH}Cl{(PPh2)CH2(PPh2)}2]Cl2 ( 6 ), which could be viewed as a Jackson–Meisenheimer complex. Complex 6 is unstable in solution and can easily be convert to the cyclic ruthenium η2‐allene complexes [Ru{CH?C(PPh3)CH?(η2‐C?CH)}Cl{(PPh2)CH2(PPh2)}2]Cl2 ( 7 ) and [Ru{CH?C(PPh3)CH?(η2‐C?CH)}Cl2{(PPh2)CH2(PPh2)}2]Cl ( 8 ). The key intermediates of the reactions have been isolated and fully characterized, further supporting the proposed mechanism for the reactions. Similar reactions also occurred in phosphonium‐substituted metallapyridinium [OsCl2{NHC(CH3)C(Ph)C(PPh3)CH}(PPh3)2]BF4 to give the cyclic osmium η2‐allene‐imine complex [OsCl2{NH?C(CH3)C(Ph)?(η2‐C?CH)}{(PPh2)CH2(PPh2)}(PPh3)]BF4 ( 11 ). 相似文献
The effect of changes in the internal energy distribution of the fragmenting ion on the ratio of metastable ion intensities for two competing fragmentation reactions has been investigated both theoretically and experimentally. Model calculations have shown that if the competing reactions have significantly different activation energies the metastable intensity ratio does depend on the internal energy distribution although large changes are necessary before the ratio changes by more than a factor of two. Experimentally the metastable characteristics of [C3H7O]+ ions of nominal structures [CH3CH2O+?CH2] (I), [(CH3)2C?O+H] (II), [CH3CH2CH?O+H] (III) and [CH3O+?CHCH3] (IV) have been examined. For each structure the metastable characteristics are found to be distinctive and independent of changes in the internal energy distribution of the fragmenting ion where these changes result from altering the precursor of the [C3H7O]+ ions. It is suggested that these internal energy changes can be estimated from the fraction of [C3H7O]+ ions which fragment in the ion-source. It is concluded that structures I to IV represent stable and distinct ionic structures. 相似文献
Triethylphosphanimine Complexes of the Acetates of Copper(II) and Zinc. Crystal Structures of [Zn(O2C–CH3)2(HNPEt3)], [Cu5(O2C–CH3)10(HNPEt3)2], and [Cu(O2C–CH3)2(HNPEt3)2] The title compounds originate from the anhydrous acetates of zinc and copper(II) with trimethylsilyl-triethylphosphanimine, Me3SiNPEt3, in the presence of water in dichloromethane. They form colourless ( 1 ), bluish-green ( 2 ), and blue ( 3 ), respectively, single crystals, which were characterized by IR spectroscopy and by crystal structure analyses. [Zn(O2C–CH3)2(HNPEt3)] ( 1 ): Space group P 4 21c, Z = 8, lattice dimensions at –83 °C: a = b = 1709.6(2), c = 982.4(1) pm, R = 0.0551. 1 has a polymeric chain structure in which the zinc atoms are μ2-bridged via the oxygen atoms of one of the two acetato groups, while the second acetato group and the phosphanimine are bonded terminally. [Cu5(O2C–CH3)10(HNPEt3)2]( 2 · 4 CH2Cl2): Space group P21/c, Z = 8, lattice dimensions at –80 °C: a = 1761.18(13), b = 4074.5(2), c = 1733.34(15) pm, β = 91.383(10)°, R = 0.0413. 2 consists of the two structural units [Cu2(O2C–CH3)4] and [Cu3(O2C–CH3)6(HNPEt3)2], which are connected via two of the acetato groups of the Cu3-unit along the crystallographic a-axis to form three crystallographically independent polymeric strands. [Cu(O2C–CH3)2(HNPEt3)2] ( 3 ): Space group P21/n, Z = 2, lattice dimensions at 20 °C: a = 695.49(8), b = 1217.85(10), c = 1380.05(7) pm, β = 96.451(7)°, R = 0.0291. 3 forms monomeric, centrosymmetric molecules with a square planar environment at the Cu atoms. 相似文献
Phosphorane Iminato Complexes of Sulfur. Syntheses and Crystal Structures of [O3SS(NPPh3)2] · CH3CN, [SO(NPPh3)2], and [SCl(NPMe3)2]Cl The title compounds have been prepared by the reaction of Me3SiNPPh3 with SO2 and SOCl2, respectively, and by the reaction of Me3SiNPMe3 with S2Cl2. They form colourless, moisture sensitive crystals, which were characterized by IR spectroscopy and by crystal structure determinations. [O3SS((NPPh3)2)] · CH3CN : Space group Pca21, Z = 4, structure solution with 4016 observed unique reflections, R = 0.050. Lattice dimensions at ?60°C: a = 1865.1, b = 1168.4, c = 1569.0 pm. The compound has a zwitterionic structure with a S? S bond length of 218.2 pm and bond lengths S? N of 161.2 and P? N of 160.1 pm. [SO(NPPh3)2] : Space group P21/c, Z = 4, structure solution with 2854 observed unique reflections, R = 0.113. Lattice dimensions at ?50°C: a = 1173.1, b = 1585.6, c = 1619.2 pm, b? = 98.13°. The compound forms monomeric molecules, in which the positions of S and N atoms are disordered in two positions. The bond lengths are S? N 166 pm and P? N 163 pm in average. [SCl(NPMe3)2]Cl : Space group P1 , Z = 2, structure solution with 2416 observed unique reflections, R = 0.038. Lattice dimensions at 20°C: a = 613.2, b = 1030.3, c = 1111.4 pm, α = 88.48°, b? = 88.01°, γ = 83.10°. The compound forms ions [SCl(NPMe3)2]+ and Cl?. In the cation the sulfur atom is ?-tetrahedrally coordinated with a long S? Cl distance of 246.9 pm and bond lengths S? N of 155.3 pm and P? N of 164.3 pm in average. 相似文献
The melting diagram of the system (CH3)4NF? HF was studied between 50 and 100 mole-% HF and from ?185°C to the respective liquidus temperatures (at most 162°C) by difference thermal analysis aided by temperature-dependent X-ray powder diffraction. The system was found to be quasi-binary with the HF-rich intermediary stable compounds (CH3)4NF · 2 HF (melting point 110°C), (CH3)4NF · 3 HF (20°C, decomposition), (CH3)4NF · 5 HF (?76°C, decomposition), and (CH3)4NF · 7 HF (?110°C, decomposition), most of which undergo solid-solid phase transitions. Crystal structures were determined of the low-temperature form of (CH3)4NF · 2 HF (stable below 83°C, orthorhombic, space group Pbca, Z = 8 formula units per unit cell), the high-temperature form of (CH3)4NF · 3 HF (stable above ?87°C, monoclinic, P2/c, Z = 4), and of (CH3)4NF · 5 HF (tetragonal, I4 , Z = 2). The structures are those of poly(hydrogen fluorides) (CH3)4N[HnFn+1] with homologous anions [H2F3]?, [H3F4]?, and [H5F6]?, respectively, formed by strong hydrogen bonding F? H…?F. The anion [H5F6]? is the first one of this composition established by crystal structure analysis. Its structure can be written as [(FH)2FHF(HF)2]? with four equivalent terminal hydrogen bonds of 248.4 pm and a very short central one of 226.6 pm (F…?F distances) through a 4 point of the space group. 相似文献
Reaction of the Cage-like Silicic Acid Derivative [(CH3)2HSi]8Si8O20 with Unsaturated Organic Compounds By 29Si, 1H, and 13C NMR investigations were shown that the eight HSi?groups of the double four-ring silicic acid derivative [(CH3)2HSi]8Si8O20 react with the following unsaturated compounds: vinylcyclohexene, allyl glycidyl ether, methyl methacrylate, octadecene-1, and styrene. The resulting oily products are soluble in organic solvents. The compounds were characterized by the chemical shifts of the 29Si, 1H, and 13C NMR signals. Their formulae are [C6H9(CH2)2Si(CH3)2]8Si8O20, [CH3OOCCH(CH3)CH2Si(CH3)2]8Si8O20, [CH3(CH2)17Si(CH3)2]8Si8O20 and [C6H5(CH2)2Si(CH3)2]8Si8O20, and [C6H5CH(CH3)Si(CH3)2]8 Si8O20, respectively. Mainly the addition reactions do not follow the Markovnikov rule. 相似文献
Contributions to the Chemistry of Transition Metal Alkyl Compounds. XL. About Lithium Alkenylmanganates(II) MnCl2 reacts with vinyl, 2,2-dimethylvinyl, allyl, and methallyl lithium giving rise to alkenyl manganates(II). In a pure state the compounds Li2[Mn(CH?CH2)4] · 1.5 diox, Li2[Mn(CH?C(CH3)2)4] · 1.5 diox, Li2[Mn(CH2? CH?CH2)4] · 2.5 diox and Li3[Mn(CH2? C(CH3)?CH2)5] · 2 diox were isolated. The compounds were characterized by elementary analysis, EPR and IR spectra, magnetic moments, and reactions with iodine. 相似文献
The reactivity of the [MoV2O4]2+ dinuclear unit with the [O3P(C(CH3)(OH))PO3]4? etidronate ligand has been investigated. Three complexes have been isolated and characterized by IR spectroscopy, elemental analysis and single crystal X-Ray diffraction studies. Structural determination of the tetranuclear compound (CN3H6)6[(MoV2O4)2(O3P(C(CH3)O)PO3)2]·12H2O (1) revealed that the hydroxo group of the etidronate ligand can be deprotonated in presence of MoV even in acidic media. It follows that its coordination mode thus differs from that of the methylenediphosphonate ligand [O3P(CH2)PO3]4?, which reactivity with MoV has been previously widely studied. In contrast, no such deprotonation of the hydroxo group is observed in the (NH4)18[(MoV2O4)6(OH)6(O3P(C(CH3)(OH))PO3)6]·35H2O complex 2. This species contains a dodecanuclear core analogous to the one previously found in the [(MoV2O4)6(OH)6(O3PCH2PO3)6]18? methylenediphosphonato polyanion. In 2, six interconnected {(MoV2O4)(O3P(C(CH3)(OH))PO3)} units form a cyclohexane-like ring in a chair conformation. In the (CN3H6)18Na3[(MoV2O4)7(O3P(C(CH3)(OH))PO3)7(CH3COO)7]·5CH3COONa 52H2O compound 3, seven {(MoV2O4)(O3P(C(CH3)(OH))PO3)(CH3COO)} units are connected, forming an almost planar tetradecanuclear wheel. This compound represents the largest homometallic MoV polyoxometalate cyclic system reported to date. Finally, 31P NMR studies revealed that only complex 1 is stable in aqueous solution. 相似文献
Contributions to the Chemistry of Organo Transition Metal Compounds. XLIX. Reactions of Cerium(IV) Acetylacetonate with Organolithium and Organomagnesium Compounds Reacting Ce(acac)4 with lithium organyls RLi (R = CH3 1-Nor1), ((CH3)2NCH2CH2CH2) in the molar ratio 1:1 the cerium compound is reduced with formation of Li[Ce(acac)4]. Using a molar ratio of Ce:Li = 1:4 organocerium complexes of the composition R3Ce · 3 Li(acac) or Li3[R3Ce(acac)3] are formed. From reactions with excess CH3Li (Ce: Li = 1:7) Li3[Ce(CH3)6] · 3 Li(acac) could be isolated. All cerium complexes are characterized by elementary analysis, hydrolysis products, i.r. spectra, and molecular weight determination. 相似文献
Tetrakis(p‐tolyl)oxalamidinato‐bis[acetylacetonatopalladium(II)] ([Pd2(acac)2(oxam)]) reacted with Li–C≡C–C6H5 in THF with formation of [Pd(C≡C–C6H5)4Li2(thf)4] ( 1a ). Reaction of [Pd2(acac)2(oxam)] with a mixture of 6 equiv. Li–C≡C–C6H5 and 2 equiv. LiCH3 resulted in the formation of [Pd(CH3)(C≡C–C6H5)3Li2(thf)4] ( 2 ), and the dimeric complex [Pd2(CH3)4(C≡C–C6H5)4Li4(thf)6] ( 3 ) was isolated upon reaction of [Pd2(acac)2(oxam)] with a mixture of 4 equiv. Li–C≡C–C6H5 and 4 equiv. LiCH3. 1 – 3 are extremely reactive compounds, which were isolated as white needles in good yields (60–90%). They were fully characterized by IR, 1H‐, 13C‐, 7Li‐NMR spectroscopy, and by X‐ray crystallography of single crystals. In these compounds Li ions are bonded to the two carbon atoms of the alkinyl ligand. 1a reacted with Pd(PPh3)4 in the presence of oxygen to form the already known complexes trans‐[Pd(C≡C–C6H5)2(PPh3)2] and [Pd(η2‐O2)(PPh3)2]. In addition, 1a is an active catalyst for the Heck coupling reaction, but less active in the catalytic Sonogashira reaction. 相似文献
