The First Structurally Characterized Mn(III) Substituted Sandwich-type Polyoxotungstates

The new polyoxotungstates H₂O (1), · 28H₂O (2) and H₂O (3) were synthesized in aqueous solution and characterized by IR and Raman spectroscopy, energy dispersive X-ray fluorescence and single-crystal X-ray analysis. The anions in 1 and 2 are the first structurally characterized sandwich-type polyoxoanions which contain trivalent manganese atoms. The manganese atoms are coordinated by four oxygen atoms of two Keggin fragments and one water molecule, forming a square pyramid. The manganese(II) containing anions in 3 are linked via Mn–O–W-bonds, forming a two-dimensional network.Dedicated to Prof. M.T. Pope on the occasion of his retirement.     

Counter-Ion Association Effect in Dilute Giant Polyoxometalate [AsIII 12CeIII 16(H2O)36W148O524]76−({W148}) and [Mo132O372(CH3COO)30 (H2O)72]42− ({Mo132}) Macroanionic Solutions

This article reports the use of simple conductivity measurements to explore the state of small counter-ions (mostly NH ₄ ⁺ and Na⁺) in $[\hbox{As}^{\rm III}_{12}\hbox{Ce}^{\rm III}_{16}(\hbox{H}_2\hbox{O})_{36}\hbox{W}_{148}\hbox{O}_{524}]^{76-} (\{\hbox{W}_{148}\})$ and $[\hbox{Mo}_{132}\hbox{O}_{372}(\hbox{CH}_{3}\hbox{COO})_{30} (\hbox{H}_{2}\hbox{O})_{72}]^{42-} (\{\hbox{Mo}_{132}\})$ macroanionic solutions. All the solutions are dialyzed to remove the extra electrolytes. Conductivity measurements on {(NH₄)₇₀Na₆W₁₄₈} and {(NH₄)₄₂Mo₁₃₂} solutions at different concentrations both before and after dialysis indicate that the state of counter-ions has obvious concentration dependence. The “counter-ion association” phenomenon, that is, some small counter-ions closely associate with macroanions and move together, has been observed in both types of macroionic solutions above certain concentration. The association of counter-ions in hydrophilic macroionic solutions provides support on our previous speculation that the counter-ions might be responsible for the unique self-assembly of such macroanions into single-layer blackberry-type structures.     

Cluster Oxalate Complexes [W3(μ3-Q)(μ2-Q)3 (C2O4)3(H2O)3]2? (Q=S, Se): Mechanochemical Synthesis and Crystal Structure

Mechanochemical reaction of cluster coordination polymers (Q=S, Se) with solid leads to the cluster core excision with the formation of anionic complexes . Extraction of the reaction mixture with water followed by crystallization gives crystalline (main product) and (1) (minor product). In the case of the Se cluster, the complex could not be isolated, and the treatment of the aqueous extract with PPh₃ gave (2) in a low yield. Alternatively, it was obtained from and in high yield. Both 1 and 2 were characterized by X-ray structure analysis. Dedicated to Academician I. I. Moiseev on the occasion of his 75th birthday and in recognition of his outstanding contribution to cluster chemistry.     

Two Group 8 Carbonyl Clusters Containing a Naked {\varvec{\mu}}_5-Sb Atom

The synthesis and structural characterisation of two novel clusters, 2, and 3, are presented. They are the first examples of osmium and ruthenium clusters containing a naked atom.     

Reactions of V-Substituted Polyoxometalates with L-Cysteine

Three polyoxometalates (POMs), (X=P or As) and , in their oxidized and reduced forms, were selected for direct reaction or electrocatalytic reaction with L-cysteine, because they have the most negative formal potentials among those POMs active for the desired reaction. The good linearity of the UV–Visible calibration curve obtained for the reaction of α₂-[P₂V^VW₁₇O₆₂]⁷⁻ with L-cysteine indicates both a simple 1:1 stoichiometry for the process and the possibility to select a wavelength domain in which the one-electron reduced forms of this POM is the only strongly absorbing species in the mixture. Another general result among the three selected POMs is the existence, in each example, of a sharp isosbestic point during the recording of individual spectrakinetics using a photodiode array system. The kinetics could be fitted accuretely to a mono-exponential rate equation and the rate constants were determined. Electrocatalysis of the oxidation of L-cysteine was carried out in the presence of α₂-[H₄P V^IVW₁₇O₆₂]⁹⁻ as an example. The rate constant measured by chronocoulometry for this system compares favourably with that extracted from stopped flow experiments.Dedicated in honor of Professor Michael T. Pope on the occasion of his retirement.     

Pd(PBu 3 t ) Adducts of Os3(CO)12. Synthesis and Structures of Pd2Os3(CO)12(PBu 3 t )2 and Pd3Os3(CO)12 (PBu 3 t )3

Two new compounds Pd₂Os₃(CO)₁₂ , 13 and Pd₃Os₃(CO)₁₂ , 14 have been obtained from the reaction of with Os₃(CO)₁₂ at room temperature. The products were formed by the addition of two and three groups to the Os–Os bonds of Os₃(CO)₁₂. Compounds 13 and 14 interconvert between themselves by intermolecular exchange of the groups in solution. Compounds 13 and 14 have been characterized by single crystal X-ray diffraction analyses.Dedicated to Professor Brian F. G. Johnson on the occasion of his retirement – 2005.     

Solid-state Structures and Solution Behavior of Alkali Salts of the [\hbox{Nb}_{6}\hbox{O}_{19}]^{8-} Lindqvist Ion

The hexaniobate Lindqvist ion has long been known as the dominant specie in alkaline niobium oxide solutions. Recent advances in heteropolyniobate chemistry continue to be greatly aided by use of alkali salts as soluble precursors; in particular, potassium, sodium and lithium hexaniobate salts. We report here the solid-state characterization and solution behavior of Li, K, Rb and Cs Lindqvist salts. Synthesis and single-crystal X-ray diffraction data is reported for nine new hexaniobate salts. These structures differ in the number of charge-balancing alkali cations, protonation of the clusters, relative arrangement of the clusters and alkali metal cations, amount of lattice water and its mode of interaction with other lattice species. Trends of alkali-cluster bonding are observed as a function of alkali radius. Protonation of the clusters in the solid-state is influenced by the method of crystallization of the salt. Lability of the cluster oxygens is observed by solution ¹⁷O NMR experiments. Rates of isotopic enrichment of the bridging oxygen, terminal oxygen and bridging hydroxyl cluster sites are compared for aqueous solutions of Li, K, Rb and Cs hexaniobate salts. Parameters influencing the oxo-ligand exchange rates of the salts are discussed relative to their use as heteropolyniobate precursors.This paper is dedicated to Professor Michael T. Pope on the event of his retirement to acknowledge his fruitful career in polyoxometalate chemistry.     

Photoreduction of Thiosulfate in Semiconductor Dispersions

Conduction band electrons produced by band gap excitation of TiO₂-particles reduce efficiently thiosulfate to sulfide and sulfite. \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm 2e}_{{\rm cb}}^ - ({\rm TiO}_{\rm 2}) + {\rm S}_{\rm 2} {\rm O}_3^{2 - } \longrightarrow {\rm S}^{2 - } + {\rm SO}_3^{2 - } $\end{document} This reaction is confirmed by electrochemical investigations with polycrystalline TiO₂-electrodes. The valence band process in alkaline TiO₂-dispersions involves oxidation of S₂O to tetrathionate which quantitatively dismutates into sulfite and thiosulfate, the net reaction being: \documentclass{article}\pagestyle{empty}\begin{document}$ 2{\rm h}^{\rm + } ({\rm TiO}_{\rm 2}) + 0.5{\rm S}_{\rm 2} {\rm O}_{\rm 3}^{{\rm 2} - } + 1.5{\rm H}_{\rm 2} {\rm O} \longrightarrow {\rm SO}_3^{2 - } + 3{\rm H}^{\rm + } $\end{document} This photodriven disproportionation of thiosulfate into sulfide and sulfite: \documentclass{article}\pagestyle{empty}\begin{document}$ 1.5{\rm H}_{\rm 2} {\rm O } + 1.5{\rm S}_{\rm 2} {\rm O}_{\rm 3}^{{\rm 2} - } \mathop \to \limits^{h\nu} 2{\rm SO}_3^{2 - } + {\rm S}^{{\rm 2} - } + 3{\rm H}^{\rm + } $\end{document} should be of great interest for systems that photochemically split hydrogen sulfide into hydrogen and sulfur.     

Experimental Research of OH and N<Stack><Subscript>2</Subscript><Superscript>+</Superscript></Stack> Spatially Resolved Spectra in a Needle-Plate Pulsed Streamer Discharge

In this study, the spatial distributions of the emission intensity of OH (\(\hbox{A}^{2}\Upsigma {\rightarrow}\hbox{X}^{2}\Uppi,\) 0-0) and \(\hbox{N}_{2}^{+} (\hbox{B}^{2}\Upsigma_{\rm u}^{+}\rightarrow \hbox{X}^{2}\Upsigma_{\rm g}^{+},\) 0-0, 391.4 nm) are investigated in the atmospheric pressure pulsed streamer discharge of H₂O and N₂ mixture in a needle-plate reactor configuration. The effects of pulsed peak voltage, pulsed repetition rate, input power, and O₂ flow rate on the spatial distributions of the emission intensity of OH (\(\hbox{A}^{2}\Upsigma {\rightarrow}\hbox{X}^{2}\Uppi,\) 0-0), \(\hbox{N}_{2}^{+} (\hbox{B}^{2}\Upsigma _{\rm u}^{+} \rightarrow \hbox{X}^{2}\Upsigma _{\rm g}^{+},\) 0-0, 391.4 nm), and the vibrational temperature of N₂ (C) in the lengthwise direction from needle to plate are attained. It is found that the emission intensities of OH (\(\hbox{A}^{2}\Upsigma {\rightarrow}\hbox{X}^{2}\Uppi,\) 0-0) and \(\hbox{N}_{2}^{+} (\hbox{B}^{2}\Upsigma_{\rm u}^{+} \rightarrow \hbox{X}^{2}\Upsigma_{\rm g}^{+},\) 0-0, 391.4 nm) rise with increasing the pulsed peak voltage, the pulsed repetition rate and the input power, and decrease with increasing O₂ flow rate. In the direction from needle to plate, the emission intensity of OH (\(\hbox{A}^{2}\Upsigma {\rightarrow}\hbox{X}^{2}\Uppi,\) 0-0) decreases firstly, and rises near the plate electrode, while the emission intensity of \(\hbox{N}_{2}^{+}(\hbox{B}^{2}\Upsigma_{\rm u}^{+} \rightarrow \hbox{X}^{2}\Upsigma_{\rm g}^{+},\) 0-0, 391.4 nm) is nearly constant along the needle to plate direction firstly, and rises sharply near the plate electrode. The vibrational temperature of N₂ (C) is almost independent of the pulsed peak voltage and the pulsed repetition rate, but rises with increasing the O₂ flow rate and keeps nearly constant in the lengthwise direction. The main physicochemical processes involved are discussed.     

Determination of the Distribution of Cobalt-Chloro Complexes in Hydrochloric Acid Solutions at 298 K

Knowledge of the distribution of metal-chloro complexes in hydrochloric acid solutions is fundamental for understanding the anion-exchange reaction. Anion-exchange separation allows ultrahigh purification during hydrometallurgical processes. However, at present the exchange reactions are not understood in detail. A more sophisticated purification needs improvement of the anion-exchange separation process. The process is based upon anion-exchange reactions and the distribution of metal-chloro complexes. The present work deals with cobalt-chloro complexes which exhibit a beautiful deep blue color in a concentrated hydrochloric acid solution. The intensity of the absorption attributed to the deep blue color is so strong that it is hard to obtain meaningful results by factor analysis. Another absorption band was chosen to be used in factor analysis and the attempt was successful. The number of cobalt-chloro complexes in hydrochloric acid solutions was determined to be three, and the cumulative formation constants were fitted to absorption spectra decomposed by factor analysis. During the optimization of the cumulative formation constants, a modified Debye–Hückel model for estimation of the activity coefficients of \(\hbox {Cl}^{-}\) was used. It was found that there are three cobalt complexes \([\hbox {Co}^{\mathrm{II}}(\hbox {H}_{2}\hbox {O})_{6}]^{2+}\), \([\hbox {Co}^{\mathrm{II}}\hbox {Cl}(\hbox {H}_{2}\hbox {O})_{5}]^{+}\), and \([\hbox {Co}^{\mathrm{II}}\hbox {Cl}_{4}]^{2-}\), and the two cumulative formation constants were optimized such that \(\log _{10}\beta _{1} = -\,0.861\) and \(\log _{10}\beta _{4} = -\,7.40\). The geometries of the complexes are proposed by assignment of absorption bands using ligand field theory. A qualitative assessment of the relationship between the acquired distribution of cobalt-chloro complexes and the adsorption function of cobalt species from hydrochloric acid solutions to anion-exchange resin was made.     

Alternating copolymerization of dienes with α-olefins

Alternating copolymerization of butadiene with several α-olefins and of isoprene with propylene were investigated by using a mixture of VO(Acac)₂, Et₃Al, and Et₂AlCl as catalyst. The alternating copolymerization ability of the olefins decreases in the order, propylene > 1-butene > 4-methyl-1-pentene > 3-methyl-1-butene. The study on the sequence of the copolymer of isoprene with propylene by ozonolysis reveals that the polymer chain is reasonably expressed by the sequence \documentclass{article}\pagestyle{empty}\begin{document}$ \rlap{--} [{\rm CH}_{\rm 2} \hbox{--} {\rm CH} \hbox{=\hskip-1pt=} {\rm C(CH}_{\rm 3}) \hbox{--} {\rm CH}_{\rm 2} \hbox{--} {\rm CH(CH}_{\rm 3}) \hbox{--} {\rm CH}_{\rm 2} \rlap{--}]_n $\end{document}. NMR and infrared spectra indicate that the chain is terminated with propylene unit, forming a structure of ?C(CH₃)? CH₂? C(CH₃)?CH₂ involving a vinylene group.     

Formation of hydrates from asymmetric and cyclic ketones in their oxidation by alkaline hexacyanoferrate(III)

Abstract  Alkaline hexacyanoferrate(III) oxidizes 2-methyl-3-pentanone and 2-methylcyclohexanone quite rapidly. Kinetic data show second-order kinetics with respect to hydroxide ion concentrations indicating the formation of hydrates by ketones in aqueous alkaline medium before their reaction with the oxidant. The rate follows direct proportionality with respect to the concentrations of hexacyanoferrate(III) and ketones. Externally added hexacyanoferrate(II) does not affect the reaction velocity indicating the reduction of oxidant takes place after the rate determining step. Orders with respect to various reactants were confirmed by various methods and the overall rate constant of the reaction was calculated by three different variations. Thermodynamic data suggest that 2-methyl-3-pentanone forms the activated complex more easily compared to 2-methylcyclohexanone. Graphical abstract  Second-order in [OH⁻] in the oxidation of 2-methyl-3-pentanone and methyl cyclohexanone by alkaline hexacyanoferrate (III) indicates that oxidation proceeds through the formation of hydrates. Rate constant and thermodynamic parameters at five temperatures were calculated. Mono and dicarboxylic acids were confirmedto be the final oxidation products. Rate law given was—

Studies on a new dinuclear Co<Superscript>II</Superscript>–pterin complex exhibiting reactivity towards phenylalanine and bromobenzene

2-Pivaloylamino-6-acetonyl-isoxanthopterin (1, ) has been reacted with under suitable conditions for synthesizing the new compound ] (2). It has been characterized by elemental analysis, electrospray ionization mass spectrometry, magnetic susceptibility measurement, different spectroscopic techniques, and cyclic voltammetry. Molecular mechanics (MM2) method provided with its optimized geometry (having lowest steric energy), consistent with the above data; the optimized bond lengths and bond angles data tally with the literature X-ray structural data. Reactivity of (2) towards phenylalanine in the presence of in methanol has been followed both kinetically and stoichiometrically; a reasonable amount of tyrosine could be recovered from the reaction medium. The negative value (−274.0 J mol⁻¹ indicates an associative pathway for this process. (2) is also able to react with bromobenzene as indicated by time-dependent absorption spectra as well as product identification. Efficacy of the pterin ligand residue of (2) in rendering the latter reactive towards the above-mentioned organic compounds, has been discussed on the basis of experimental evidence.     

Kinetics and mechanism of electron transfer reactions. Osmium(VIII) catalyzed oxidation of mannitol by hexacyanoferrate(III) in aqueous alkaline medium

The kinetics of electron transfer from mannitol to hexacyanoferrate(III), catalyzed by osmium(VIII), has been studied in alkaline medium. The substrate order is complex, whereas it is one with respect to the catalyst. The rate is independent of the concentration of oxidant. Also, the rate increases with increasing concentration of hydroxide ion in a complex manner. A kinetic rate law corresponding to the proposed mechanism has been suggested as follows:

High temperature polymers. I.—Sulfone ether diamines as intermediates for tractable high temperature polymers

A useful synthesis of a series of new aromatic sulfone ether diamines, H₂NC₆H₄O\documentclass{article}\pagestyle{empty}\begin{document}$\hbox{---}\hskip-5pt[\ {\rm C}_{\rm 2} {\rm H}_{\rm 4} {\rm SO}_{\rm 2} {\rm C}_{\rm 6} {\rm H}_{\rm 4} \hbox{--} {\rm ORO}\hbox{---}\hskip-5pt ]_n {\rm OC}_{\rm 6} {\rm H}_{\rm 4} {\rm SO}_{\rm 2} {\rm C}_{\rm 6} {\rm H}_{\rm 4} \hbox{---} {\rm OC}_{\rm 6} {\rm H}_{\rm 4} {\rm NH}_{\rm 2} $\end{document}, where n = 0, 1, 2…, which increases the tractability of polyimides, polyamide-imides, and polyamides, was developed. These diamines were prepared by condensing various proportions of sodium p-aminophenate, sodium bisphenates, and dichlorodiphenyl sulfone. The synthetic procedures are now refined to the point where simply coagulating these diamines into water yields high purity polymer-grade sulfone ether diamines. The latter have good tractability; and in some cases, it is possible to extrude and injection-mold these high temperature polymers.     

An investigation of the decomposition of the intermediate ions produced by electron-impact. II—[C7H7]+ ions from several halogenotoluenes

The structure and decomposition of the [C₇H₇]⁺ ions produced by electron-impact from o-, m- and p-chlorotoluene, o-, m- and p-bromotoluence, and p-iodotoluence, have been investigated. By determining the relative abundance of normal and metastable ions, these [C₇H₇]⁺ ions at electron energy of 20 eV are shown to be so-called ‘tropylium ions’. The amount of the internal energy of the [C₇H₇]⁺ ion estimated by the relative ion abundance ratios, ? [C₅H₅]⁺/[C₇H₇]⁺ and m*/[C₇H₇]⁺ for the decomposition \documentclass{article}\pagestyle{empty}\begin{document}$ [{\rm C}_{\rm 7} {\rm H}_{\rm 7}]^ + \mathop \to \limits^{m^* } [{\rm C}_{\rm 5} {\rm H}_{\rm 5}]^ + + {\rm C}_{\rm 2} {\rm H}_{\rm 2} $\end{document}, is in the order iodotoluene > bromotoluene > chlorotoluene. The heats of formation of the activated complexes for the reaction \documentclass{article}\pagestyle{empty}\begin{document}$ [{\rm C}_{\rm 7} {\rm H}_{\rm 7}]^ + \mathop \to \limits^{m^* } [{\rm C}_{\rm 5} {\rm H}_{\rm 5}]^ + + {\rm C}_{\rm 2} {\rm H}_{\rm 2} $\end{document} were estimated. The values suggest that the decomposing [C₇H₇]⁺ ions from various halogenotoluenes are identical in structure.     

Thermolytic Transformation of Organometallic Polymers Containing the Cr(CO)<Subscript>5</Subscript> Precursor into Nanostructured Chromium Oxide

Thermal treatment in air of the organometallic polymer (1) results in the formation of nanometer-size metal oxide particles. Cr particles in the 35–85 nm range, mostly 54 nm, immersed in an phosphorus oxides matrix were found. ATG studies in air suggest that the formation of the nanostructures occurs in four steps, the first involving loss of the carbonyl groups of the Cr(CO)₅ fragment. The following steps involve the oxidation of the organic matter and finally the oxidation of the chromium to give the pyrolytic product. The use of these kinds of organometallic polymers as precursors for a general and potential new route to materials having metal/metal oxide nanostructures is discussed.     

Redox Kinetics as a Probe of the Supramolecular Interaction of α- and β-Cyclodextrins with Amphiphilic Nickel(II) Complexes of Pentaazamacrocycles Bearing Aliphatic Tails

Host–guest interactions between α- and β-cyclodextrins and nickel(II) polyazamacrocycles bearing aliphatic pendant arms (n-butyl, n-octyl and n-dodecyl) have been investigated, using redox kinetics as a probe, to estimate binding constants. Electrospray mass spectrometry shows the formation of inclusion complexes in aqueous solution. Cyclic voltammetric measurements show the cyclodextrins to have no effect on the redox potentials for the nickel(II/III) couples. Kinetics of oxidation of the nickel(II) complexes to the tervalent state exhibits rate retardation in the presence of the cyclodextrins. The outer-sphere oxidation of the nickel(II) macrocycles by aqua(5, 5, 7, 12, 12, 14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-1-acetato)nickel(III), [Ni(hmca)(OH₂)]²⁺ obeys the rate law: $${ \hbox{Rate} ={k}_{\rm obs}[\hbox{Ni}^{\rm III}\hbox{(hmca)}\hbox{(OH}_{\rm 2})]=\frac{{[k}_{\rm 2} + {k}_{\rm 3}{K}_{\rm CD}\hbox{][Ni}^{\rm II}\hbox{L][Ni}^{\rm III}\hbox{(hmca)(OH}_{\rm 2}{)]}}{{(1 + K}_{\rm {CD}}\hbox{[CD])}}}$$ where k ₂ is the rate constant for oxidation of the nickel(II) macrocycle in the absence of cyclodextrins, and k ₃ is that for oxidation of the {NiL.CD} inclusion complex.     

Polymerization of hexamethylcyclotrisiloxane with a biscatecholsiliconate. I. Nature of polymerization

Polymerization behavior of hexamethylcyclotrisiloxane (D₃) in toluene solution with the use of benzyltrimethylammonium bis(o-p;henylenedioxy)phenylsiliconate as a catalyst, dimethyl sulfoxide as promoter, and adventitious moisture as initiator was investigated. The polymerization system gives a linear difunctional polymer, HO(Me₂SiO)_xH, with a molecular weight which is inversely proportional to the amount of water reacted rather than to the amount of catalyst employed. The polymerization in the presence of H₂O gives rise to molecular weight distributions very close to Poisson distributions. The normalized experimental GPC curve agrees very well with the theoretical GPC curve calculated from the polymerization scheme: \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{*{20}c} {{\rm H}_2 {\rm O} + ({\rm Me}_2 {\rm SiO})_3 \to {\rm HO}({\rm Me}_2 {\rm SiO})_3 {\rm H}} \\ {{\rm HO(Me}_{\rm 2} {\rm SiO)}_{\rm 3} {\rm H} + {\rm N(Me}_{\rm 2} {\rm SiO)}_{\rm 3} \to {\rm HO}({\rm Me}_2 {\rm SiO})_{3(n + 1)} {\rm H}} \\ \end{array} $$\end{document} Polymerization carried out in the combined presence of H₂O and ROH, where R is Me or Me₃Si, gives rise to bimodal molecular weight distributions. The resulting polymers consist of HO(Me₂SiO)_2xH and RO(Me₂SiO)_xH. The molecular weight of the former is twice that of the latter, and their proportion depends on the ratio of H₂O to ROH. The system is a special type of “living” polymer.     

Polymerization of σ-bonded organo-transition metal derivatives of styrene

Five new monomers of transition metal complexes containing a styryl group, trans-\documentclass{article}\pagestyle{empty}\begin{document}$ {\rm Pd}({\rm PBu}_{\rm 3})_2 \rlap{--} ({\rm C}_6 {\rm H}_4 {\rm CH} \hbox{=\hskip-2pt=} {\rm CH}_2 ){\rm X\ X \hbox{=\hskip-2pt=} Cl(Ia),\ X \hbox{=\hskip-2pt=} Br(Ib)},\ {\rm X \hbox{=\hskip-2pt=} CN(Ic),\ X \hbox{=\hskip-2pt=} Ph(Id)} $\end{document} and trans-\documentclass{article}\pagestyle{empty}\begin{document}${\rm Pt(PBu}_{\rm 3} {\rm )}_{\rm 2} \rlap{--} ({\rm C}_{\rm 6} {\rm H}_{\rm 4} {\rm CH} \hbox{=\hskip-2pt=} {\rm CH}_2 ){\rm Cl}({\rm II})$\end{document}, were synthesized. The monomers were readily homopolymerized in benzene with the use of AIBN or BBu₃–oxygen as the initiator. Copolymerization of Ia with styrene was carried out by using AIBN. From the Cl content of the copolymers by analysis, monomer reactivity ratios and Q–e values were obtained as follows: r₁ = 1.49, r₂ = 0.45; Q₂ = 0.41, e₂ = ?1.4 (M₁ = styrene, M₂ = Ia). Based on the above data, the σ-bonded palladium moiety at para position of styrene acts as a strongly electron-donating group to the phenyl ring. This is also supported by the olefinic β-carbon chemical shift of ¹³C NMR for Ia.