Anharmonic Effect of the Unimolecular Dissociation of Ethyl Radical

The anharmonic and harmonic rate constants have been calculated for the unimolecular dissociation of ethyl radical using the method proposed by Yao and Lin (YL method) at both B3LYP/6‐311++G** and MP2/6‐311++G** levels. The different rate constants indicate that the results obtained from B3LYP and MP2 method are very close. The anharmonic and tunneling effect of the title reaction has also been examined. The comparison shows that, both in microcanonical and canonical systems, the anharmonic rate constants are higher than those for harmonic cases, especially in the case of high total energies and temperatures, which indicates that anharmonic effect of the unimolecular dissociation of ethyl into C₂H₄ and H is so significant that cannot be neglected. The tunneling effect is very small for the decomposition of C₂H₅ radical.     

Anharmonic Effect in CH<Subscript>3</Subscript>CH<Subscript>2</Subscript>C(=O)OCH<Subscript>2</Subscript>CH<Subscript>3</Subscript> Decomposition

In this paper, using the B3LYP functional and CCSD(T) method with 6-311++G** basis set, the harmonic and anharmonic rate constants in the unimolecular dissociation of ethyl propanoate have been calculated using Rice–Ramsperger–Kassel–Marcus theory. The anharmonic rate constants of the title reaction have also been examined, the comparison shows that, the anharmonic effect especially in the case of high total energies and temperature for channels 3 to 6 is significant, so that the anharmonic effect cannot be neglected for unimolecular dissociation reaction of CH₃CH₂C(=O)OCH₂CH₃ both in microcanonical and canonical systems.     

Pd(II) complexes of Schiff bases and their application as catalysts in Mizoroki–Heck and Suzuki–Miyaura cross‐coupling reactions

Schiff bases of 2‐(phenylthio)aniline, (C₆H₅)SC₆H₄N?CR (R = (o‐CH₃)(C₆H₅), (o‐OCH₃)(C₆H₅) or (o‐CF₃)(C₆H₅)), and their palladium complexes (PdLCl₂) were synthesized. The compounds were characterized using ¹H NMR and ¹³C NMR spectroscopy and micro analysis. Also, electrochemical properties of the ligands and Pd(II) complexes were investigated in dimethylformamide–LiClO₄ solution with cyclic and square wave voltammetry techniques. The Pd(II) complexes showed both reversible and quasi‐reversible processes in the ?1.5 to 0.3 V potential range. The synthesized Pd(II) complexes were evaluated as catalysts in Mizoroki–Heck and Suzuki–Miyaura cross‐coupling reactions. Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis of poly(1‐chloro‐2‐arylacetylene)s with high cis‐content and examination of their absorption/emission properties

A series of 1‐chloro‐2‐arylacetylenes [Cl‐C?C‐Ar, Ar = C₆H₅ ( 1 ), C₆H₄‐p‐i Pr ( 2 ), C₆H₄‐p‐Oi Pr ( 3 ), C₆H₄‐p‐NHC(O)Ot Bu ( 4 ), and C₆H₄‐o‐i Pr ( 5 )] were polymerized using (tBu₃P)PdMeCl/silver trifluoromethanesulfonate (AgOTf) and MoCl₅/SnBu₄ catalysts. The corresponding polymers [poly( 1 )–poly( 5 )] with weight‐average molecular weights of 6,500–690,000 were obtained in 10–91% yields. THF‐insoluble parts, presumably high‐molecular weight polymers, were formed together with THF‐soluble polymers by the Pd‐catalyzed polymerization. The Pd catalyst polymerized nonpolar monomers 1 and 2 to give the polymers in yields lower than the Mo catalyst, while the Pd catalyst polymerized polar monomers 3 and 4 to give the corresponding polymers in higher yields. The ¹H NMR and UV–vis absorption spectra of the polymers indicated that the cis‐contents of the Pd‐based polymers were higher than those of the Mo‐based polymers, and the conjugation length of the Pd‐based polymers was shorter than that of the Mo‐based polymers. Pd‐based poly( 5 ) emitted fluorescence most strongly among poly( 1 )–poly( 5 ). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 382–388     

Computational Study on the Thermal Decomposition of Phenol‐Type Monolignols

A detailed chemical kinetic model has been developed to theoretically predict the pyrolysis behavior of phenol‐type monolignol compounds (1‐(4‐hydroxyphenyl)prop‐2‐en‐1‐one, HPP; p‐coumaryl alcohol, 3‐hydroxy‐1‐(4‐hydroxyphenyl)propan‐1‐one, HHPP; 1‐(4‐hydroxyphenyl)propane‐1,3‐diol, HPPD) released from the primary heterogeneous pyrolysis of lignin. The possible thermal decomposition pathways involving unimolecular decomposition, H‐addition, and H‐abstraction by H and CH₃ radicals were investigated by comparing the activation energies calculated at the M06–2X/6–311++G(d,p) level of theory. The results indicated that all phenol‐type monolignol compounds convert to phenol by side‐chain cleavage. p‐Coumaryl alcohol decomposes into phenol via the formation of 4‐vinylphenol, whereas HPP, HHPP, and HPPD decompose into phenol via the formation of 4‐hydroxybenzaldehyde. The pyrolytic pathways focusing on the reactivity of the hydroxyl group in HPP and producing cyclopentadiene (cyc‐C₅H₆) were also investigated. The transition state theory (TST) rate constants for all the proposed elementary reaction channels were calculated at the high‐pressure limit in the temperature range of 300–1500 K. The kinetic analysis predicted the two favorable unimolecular decomposition pathways in HPP: the one is the dominant channel below 1000 K to produce cyc‐C₅H₆, and the other is above 1000 K to yield phenol (C₆H₅OH).     

Anharmonic Effect of the Unimolecular Dissociation of HFCO and DFCO

The unimolecular reactions of HFCO and DFCO have been studied by RRKM theory. The harmonic and anharmonic rate constants of the HFCO and DFCO decompositions have been calculated. The harmonic and anharmonic rate constants increase with the increasing temperatures and total energies both in the canonical and microcanonical systems. The comparison shows that the rate constants of DFCO decomposition are lower than that of the HFCO decomposition. The anharmonic effect and isotope effect have also been investigated. It has been found that the anharmonic effect and isotope effect are not significant either in the canonical or microcanonical system for all the reactions.     

Formation and stability of gaseous tolyl ions

Collisional activation mass spectra confirm that tolyl ions can be produced from a variety of CH₃C₆H₄Y compounds. High purity o-, m- and p-tolyl ions are prepared by chemical ionization of the corresponding fluorides (Y=F) as proposed by Harrison. In electron ionization of CH₃C₆H₄Y formation of the more stable tropylium and benzyl ionic isomers usually accompanies that of the o-, m- and p-tolyl ions. Isomerization of low energy [CH₃C₆H₄Y]⁺? to [Y–methylenecyclohexadiene]⁺? is proposed to account for most [benzyl]⁺ formation, while the tropylium ion appears to arise from the isomerization of tolyl ions formed with higher internal energies, [o-, m-, p-tolyl]⁺→ [benzyl]⁺→ [tropylium]⁺, consistent with Dewar's predictions from MINDO/3 calculations.     

A Computational Understanding of Solvent Effect on the Structure,Electronic, Thermochemical,and Spectroscopic Properties of Ni(η2‐C6H4)(H2PCH2CH2PH2) Complex

Here we report the density functional calculations of the molecular parameters including the energy, geometries, electric dipole moments, vibrational IR frequencies, and ¹H and ¹³C NMR chemical shifts of Ni(η²‐C₆H₄ )(H₂PCH₂CH₂PH₂ ) (a benzyne complex). Based on the polarizable continuum model (PCM ), the effect of polarity of the solvent on these parameters was explored. The wavenumbers of υ(C1–C2 ) as well as the ¹H and ¹³C NMR chemical shift values of complex in various solvents were calculated and correlated with the Kirkwood–Bauer–Magat equation (KBM ), the solvent acceptor numbers (ANs ), and the linear solvation energy relationship (LSER ). The bonding interaction between the benzyne and Ni(H₂PCH₂CH₂PH₂ ) fragment was analyzed by means of the energy decomposition analysis (EDA ). The character of the Ni–C bonds of the molecules was analyzed by natural bond orbital (NBO ) analysis. Also, Monte Carlo simulations were used for the calculation of the total energy and solvation free energy of the complex in water.     

Application of HSQC in the delineation of NMR signals of E and Z isomers of octadecyl p‐coumarates

Octadecyl p‐coumarates undergo E–Z isomerization in daylight. Although ¹H NMR, ¹³C NMR and ¹H–¹H COSY gave indications about this isomerization, the overlapping of some signals in the ¹H NMR of aromatic region prevented the delineation of signals of the individual isomers. However, heteronuclear spin quantum coupling correlation (HSQC) with the unique feature of two sets of nearby δ_C–δ_H correlations gave conclusive evidence for this isomerization and helped in the delineation of ¹H NMR and ¹³C NMR signals of E‐octadecyl p‐coumarate and Z‐octadecyl p‐coumarate. Copyright © 2012 John Wiley & Sons, Ltd.     

Luminescent Amphiphilic 2,6‐Bis(1,2,3‐triazol‐4‐yl)pyridine?Platinum(II) Complexes: Synthesis,Characterization, Electrochemical,Photophysical, and Langmuir–Blodgett Film‐Formation Studies

A new series of platinum(II) complexes with tridentate ligands 2,6‐bis(1‐alkyl‐1,2,3‐triazol‐4‐yl)pyridine and 2,6‐bis(1‐aryl‐1,2,3‐triazol‐4‐yl)pyridine (N7R), [Pt(N7R)Cl]X ( 1 – 7 ) and [Pt(N7R)(C?CR′)]X ( 8 – 17 ; R=n‐C₄H₉, n‐C₈H₁₇, n‐C₁₂H₂₅, n‐C₁₄H₂₉, n‐C₁₈H₃₇, C₆H₅, and CH₂‐C₆H₅; R′=C₆H₅, C₆H₄‐CH₃‐p_, C₆H₄‐CF₃‐p, C₆H₄‐N(CH₃)₂‐p, and cholesteryl 2‐propyn‐1‐yl carbonate; X=OTf^?, PF₆^?, and Cl^?), has been synthesized and characterized. Their electrochemical and photophysical properties have also been studied. Two amphiphilic platinum(II)? 2,6‐bis(1‐dodecyl‐1,2,3‐triazol‐4‐yl)pyridine complexes ( 3‐Cl and 8 ) were found to form stable and reproducible Langmuir–Blodgett (LB) films at the air/water interface. These LB films were characterized by the study of their surface‐pressure–molecular‐area (π–A) isotherms, XRD, and IR and polarized‐IR spectroscopy.     

Two ZnII‐based MOFs constructed with biphenyl‐2,2′,5,5′‐tetracarboxylic acid and flexible N‐donor ligands: syntheses,structures and properties

Two new Zn²⁺‐based metal–organic frameworks (MOFs) based on biphenyl‐2,2′,5,5′‐tetracarboxylic acid, i.e. H₄(o,m‐bpta), and N‐donor ligands, namely, poly[[(μ₄‐biphenyl‐2,2′,5,5′‐tetracarboxylato)bis{[1,3‐phenylenebis(methylene)]bis(1H‐imidazole)}dizinc(II)] dimethylformamide monosolvate dihydrate], {[Zn₂(C₁₆H₆O₈)(C₁₄H₁₄N₄)₂]·C₃H₇NO·2H₂O}_n or {[Zn₂(o,m‐bpta)(1,3‐bimb)₂]·C₃H₇NO·2H₂O}_n ( 1 ) {1,3‐bimb = [1,3‐phenylenebis(methylene)]bis(1H‐imidazole)}, and poly[[(μ₄‐biphenyl‐2,2′,5,5′‐tetracarboxylato)bis{[1,4‐phenylenebis(methylene)]bis(1H‐imidazole)}dizinc(II)] monohydrate], {[Zn₂(C₁₆H₆O₈)(C₁₄H₁₄N₄)₂]·H₂O}_n or {[Zn₂(o,m‐bpta)(1,4‐bimb)₂]·H₂O}_n ( 2 ) {1,4‐bimb = [1,4‐phenylenebis(methylene)]bis(1H‐imidazole)}, have been synthesized under solvothermal conditions. The complexes were characterized by IR spectroscopy, elemental analysis, single‐crystal X‐ray diffraction and powder X‐ray diffraction analysis. Structurally, the (o,m‐bpta)^4? ligands are fully deprotonated and combine with Zn²⁺ ions in μ₄‐coordination modes. Complex 1 is a (3,4)‐connected porous network with honeycomb‐like [Zn₂(o,m‐bpta)]_n sheets formed by 4‐connected (o,m‐bpta)^4? ligands. Complex 2 exhibits a (2,4)‐connected network formed by 4‐connected (o,m‐bpta)^4? ligands linking Zn²⁺ ions in left‐handed helical chains. The cis‐configured 1,3‐bimb and 1,4‐bimb ligands bridge Zn²⁺ ions to form multi‐membered [Zn₂(bimb)₂] loops. Optically, the complexes show strong fluorescence and display larger red shifts compared to free H₄(o,m‐bpta). Complex 2 shows ferroelectric properties due to crystallizing in the C_2v polar point group.     

Theoretical studies of cyclopropylsilylenes: The structures and stability of cyclopropylsilylene C3H5SiH

Ab initio molecular orbital calculations at the G2(MP2) level have been carried out on cyclopropylsilylene C₃H₅SiH. Four equilibrium structures were located. Like H₂Si, the ground state of C₃H₅SiH is singlet and the triplet is the low‐lying excited state. The singlet–triplet separation energy is 127.9 kJ/mol. The cis‐trans isomerization path of singlet cyclopropylsilylene was investigated by intrinsic reaction coordinate (IRC) calculations. The calculations show that no gauche conformers exist along the potential energy curve of the cis‐trans isomerization and the isomerization happens with a barrier of 30.1 kJ/mol. Changes (ΔH and ΔG) in thermodynamic functions, equilibrium constant K(T), and A factor and reaction rate constant k(T) in Eyring transition state theory of the cis‐trans isomerization were also calculated. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001     

Luminescent Amphiphilic 2,6‐Bis(1‐alkylpyrazol‐3‐yl)pyridyl Platinum(II) Complexes: Synthesis,Characterization, Electrochemical,Photophysical, and Langmuir–Blodgett Film Formation Studies

Two series of novel platinum(II) 2,6‐bis(1‐alkylpyrazol‐3‐yl)pyridyl (N5Cn) complexes, [Pt(N5Cn)Cl][X] ( 1 – 9 ) and [Pt(N5Cn)(C?CR)][X] ( 10 – 13 ) (X=trifluoromethanesulfonate (OTf) or PF₆; R=C₆H₅, C₆H₄‐p‐CF₃ and C₆H₄‐p‐N(C₆H₅)₂), with various chain lengths of the alkyl groups on the nitrogen atom of the pyrazolyl units have been successfully synthesized and characterized. Their electrochemical and photophysical properties have been studied. Some of their molecular structures have also been determined by X‐ray crystallography. Two amphiphilic platinum(II) 2,6‐bis(1‐tetradecylpyrazol‐3‐yl)pyridyl (N5C14) complexes, [Pt(N5C14)Cl]PF₆ ( 7 ) and [Pt(N5C14)(C?CC₆H₅)]PF₆ ( 13 ), were found to form stable and reproducible Langmuir–Blodgett (LB) films at the air–water interface. The characterization of such LB films has been investigated by the study of their surface pressure–area (π–A) isotherms, UV/Vis spectroscopy, XRD, X‐ray photoelectron spectroscopy (XPS), FTIR, and polarized IR spectroscopy. The luminescence property of 13 in LB films has also been studied.     

Ab initio study of C4H3 potential energy surface and reaction of ground‐state carbon atom with propargyl radical

The potential energy surface for the reaction of the ground‐state carbon atom [C(³P_j)] with the propargyl radical [HCCCH₂(X²B₁)] is investigated using the G2M(RCC,MP2) method. Numerous local minima and transition states for various isomerization and dissociation pathways of doublet C₄H₃ are studied. The results show that C(³P_j) attacks the π system of the propargyl radical at the acetylenic carbon atom and yields the n‐C₄H₃(²A′) isomer i3 after an 1,2‐H atom shift. This intermediate either splits a hydrogen atom and produces singlet diacetylene, [HCCCCH ( p1 )+H] or undergoes (to a minor amount) a 1,2‐H migration to i‐C₄H₃(²A′) i5 , which in turn dissociates to p1 plus an H atom. Alternatively, atomic carbon adds to the triple C?C bond of the propargyl radical to form a three‐member ring C₄H₃ isomer i1 , which ring opens to i3 . Diacetylene is concluded to be a nearly exclusive product of the C(³P_j)+HCCCH₂ reaction. At the internal energy of 10.0 kcal/mol above the reactant level, Rice–Ramsperger–Kassel–Marcus calculations show about 91.7% of HCCCCH comes from fragmentation of i3 and 8.3% from i5 . The other possible minor channels are identified as HCCCC+H₂ and C₂H+HCCH. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1522–1535, 2001     

Morphological Stable Spirobifluorene/Oxadiazole Hybrids as Bipolar Host Materials for Efficient Green and Red Electrophosphorescence

A series of 9,9′‐spirobifluorene/oxadiazole hybrids with various linkages between two components, namely SBF‐p‐OXD ( 1 ), SBF‐m‐OXD ( 2 ), and SBF‐o‐OXD ( 3 ) are designed and synthesized through Suzuki cross‐coupling reactions. The incorporation of a rigid and bulky spirobifluorene moiety greatly improves their thermal and morphological stability, with T_d (decomposition temperature) and T_g (glass transition temperature) in the ranges of 401–480 °C and 136–210 °C, respectively. 2 and 3 with meta‐ and ortho‐linkage display higher triplet energy and blue‐shifted absorption and emission than their para‐linked analogue 1 owing to the decreasing π‐conjugation between the two components. Their HOMO and LUMO energy levels depend on the linkage modes within the range of 5.57–5.64 eV and 2.33–2.49 eV, respectively. Multilayer deep red electrophosphorescent devices with 1 , 2 , 3 as hosts were fabricated and their EL efficiencies follow the order of 3 (o)> 2 (m)> 1 (p), which correlates with their triplet energy and the separation of HOMO and LUMO distributions at molecular orbitals. The maximum external quantum efficiencies of 11.7 % for green and 9.8 % for deep red phosphorescent organic light‐emitting diodes (OLEDs) are achieved by using 2 and 3 as host materials, respectively.     

Magnetisch nichtäquivalente Methylenprotonen in einigen 2-substituierten 1,3-Benzodioxanen

Zusammenfassung Die magnetische Nichtäquivalenz der Methylenprotonen in 2-R-Benzo-1,3-dioxanen, mit R=C₆H₅,o-ClC₆H₄,m-ClC₆H₄,p-ClC₆H₄,o-BrC₆H₄,m-BrC₆H₄,p-BrC₆H₄,o-NO₂C₆H₄,m-NO₂C₆H₄,p-NO₂C₆H₄,o-CH₃OC₆H₄,m-CH₃OC₆H₄,p-CH₃OC₆H₄, -Naphthyl, -Naphthyl, -Thienyl und -Thienyl, wurde in (CD₃)₂CO, CDCl₃, CCl₄, CS₂ und C₆D₆ untersucht.

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Magnetic non equivalent methylenic protons of some 2-substituted 1.3-benzodioxanes

The magnetic non equivalence of the methylenic protons in 2-R-1.3-benzodioxanes, with R=C₆H₅,o-ClC₆H₄,m-ClC₆H₄,p-ClC₆H₄,o-BrC₆H₄,m-BrC₆H₄,p-BrC₆H₄,o-NO₂C₆H₄,m-NO₂C₆H₄,p-NO₂C₆H₄,o-CH₃OC₆H₄,m-CH₃OC₆H₄,p-CH₃OC₆H₄, -naphthyl, -naphthyl, -thienyl and -thienyl were studied in (CD₃)₂CO, CDCl₃, CCl₄, CS₂ and C₆D₆.

     

Two CoII coordination polymers of biphenyl‐2,2′,5,5′‐tetracarboxylic acid with flexible N‐donor ligands: syntheses,structures and magnetic properties

Two Co^II‐based coordination polymers, namely poly[(μ₄‐biphenyl‐2,2′,5,5′‐tetracarboxylato){μ₂‐1,3‐bis[(1H‐imidazol‐1‐yl)methyl]benzene}dicobalt(II)], [Co₂(C₁₆H₆O₈)(C₁₄H₁₄N₄)₂]_n or [Co₂(o,m‐bpta)(1,3‐bimb)₂]_n ( I ), and poly[[aqua(μ₄‐biphenyl‐2,2′,5,5′‐tetracarboxylato){1,4‐bis[(1H‐imidazol‐1‐yl)methyl]benzene}dicobalt(II)] dihydrate], {[Co₂(C₁₆H₆O₈)(C₁₄H₁₄N₄)₂(H₂O)₂]·4H₂O}_n or {[Co₂(o,m‐bpta)(1,4‐bimb)₂(H₂O)₂]·4H₂O}_n ( II ), were synthesized from a mixture of biphenyl‐2,2′,5,5′‐tetracarboxylic acid, i.e. [H₄(o,m‐bpta)], CoCl₂·6H₂O and N‐donor ligands under solvothermal conditions. The complexes were characterized by IR spectroscopy, elemental analysis, single‐crystal X‐ray diffraction and powder X‐ray diffraction analysis. The bridging (o,m‐bpta)^4? ligands combine with Co^II ions in different μ₄‐coordination modes, leading to the formation of one‐dimensional chains. The central Co^II atoms display tetrahedral [CoN₂O₂] and octahedral [CoN₂O₄] geometries in I and II , respectively. The bis[(1H‐imidazol‐1‐yl)methyl]benzene (bimb) ligands adopt trans or cis conformations to connect Co^II ions, thus forming two three‐dimensional (3D) networks. Complex I shows a (2,4)‐connected 3D network with left‐ and right‐handed helical chains constructed by (o,m‐bpta)^4? ligands. Complex II is a (4,4)‐connected 3D novel network with ribbon‐like chains formed by (o,m‐bpta)^4? linkers. Magnetic studies indicate an orbital contribution to the magnetic moment of I and II due to the longer Co…Co distances. An attempt has been made to fit the χ_MT results to the magnetic formulae for mononuclear Co^II complexes, the fitting indicating the presence of weak antiferromagnetic interactions between the Co^II ions.     

Ab Initio Kinetics for Decomposition/Isomerization Reactions of C2H5O Radicals

Radical reactions : The ground‐state potential energy surface of the C₂H₅O system is investigated by ab initio methods using optimized geometries. The rate constants for the unimolecular isomerization and decomposition reactions of the three isomeric radicals (see picture) are calculated by microcanonical transition‐state theory at 200–3000 K, varying the pressures of the diluents.

     

A field ionization and collisionally activated dissociation/charge stripping study of some [C9H10]+˙ ions

The extent of isomerization of [C₉H₁₀]^+˙ ions, with lifetimes of approximately 10^?11 and 10^?6 s has been investigated using field ionization, collisionally activated dissociation and charge stripping techniques. The [C₉H₁₀]^+˙ ions which were investigated included the molecular ions of α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, indan, cyclopropylbenzene, allylbenzene and the product of water loss from 3-phenylpropanol. The field ionization spectra of all the C₉H₁₀ hydrocarbons were different indicating that isomerization to a common ion structure had not occurred to a measurable extent for ions with lifetimes of approximately 10^?11 s. Collisionally activated dissociation and charge stripping results indicated that most of the [C₉H₁₀]^+˙ ions continued to maintain unique ion structures (or mixtures of structures) at ion lifetimes of 10^?6 s. Possible exceptions are the [C₉H₁₀]^+˙ ions from allylbenzene and cyclopropylbenzene which gave indistinguishable collisionally activated dissociation and charge stripping spectra.     

Organo‐Palladium(II)‐Verbindungen mit PdC4‐Koordination: Phenylethinyl‐ und Methylphenylethinylkomplexe

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.