Synthesis and reactivity of metal-containing monomers

The polymerization of diacrylates of the nontransition metals Mg, Zn, Ba, and Pb, which proceeds at low temperatures (5–10°C) with the complexes of alkylcobalts with tridentate Shiff bases (RCo) as initiators, was studied. The radical mechanism of the process was proved with the aid of free radical scavengers. The polymerization kinetics is given by the equationW _n = k [M] · [RCo]^0.75. The influence of the nature of the metal in the monomer and the alkyl ligand in the initiator on the polymerization process was discussed. Low temperatures promote the formation of polymers with high molecular weights and a predominantly syndiotactic structure. The effect of the steric hindrances arising during polymerization due to the formation of a three-dimensional cross-linked structure in the metal-containing polymer on the microstructure of polymer chain and on polymerization kinetics was considered.For part 24 seeBull. Acad. Sci., Div. Chem. Sci., 1992, 1609.For a preliminary communication see Ref.1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 500–503, March, 1993.     

Preparation and reactivity of metal-containing monomers

The kinetics and mechanism of thermal decay of an unsaturated copper carboxylate, Cu(OCOCH=CH₂)₂ (CuAcr₂), have been studied. At 190–240°C the rate of thermal decay can be adequately described by a set of zero and first order rate equations. The initial rate of decay,W ₀, is equal to 1.7·10¹⁷exp[-48500/(RT)] s^–1. The decay products of CuAcr₂ were analyzed by IR and mass spectroscopy as well as by optical microscopy. It has been established that the thermal decay of the monomer under study is accompanied by polymerization, fragmentation, and recombination processes in the solid phase which produce polymeric agglomerates.For part 25, seeIzv.Akad.Nauk, Ser.Khim., 1993, 76 [Russ. Chem. Bull., 1993,42, 66].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 303–307, February, 1993.     

Synthesis and reactivity of metal-containing monomers 49. Synthesis and structure of low-valence transition metal acrylates and their polymers

The methods for synthesis of Cu¹⁺, Fe²⁺, Cr²⁺, and V³⁺ acrylates were elaborated. The compounds obtained were characterized by elemental analyses, data of IR, X-ray photoelectron, and Mössbauer spectroscopy, magnetochemistry, and mass spectrometry. Polymeric products were obtained by liquid-phase radical polymerization of metal acrylates. Changes in the electronic state of the ions and their nearest ligand environment during polymerization were observed.     

Synthesis and reactivity of metal-containing monomers

Optically active mixed alkoxy orthotitanates with general formula Ti(OR¹)₂(OR²)(OR³) (R¹=Et, Buⁿ; R²=CH₂CH₂OCOC(Me)=CH₂; R³=menthyl, CH(Me)CH₂Me, CH(Ph)CH(NHMe)Me, CH(C₉H₆N)(C₉H₁₄N)) were obtained for the first time by transesterification. The Ti^IV monomers synthesized were characterized by elemental analysis, ozonolysis, and¹H and¹³C NMR and IR spectroscopy. Polymer products with optical activity were obtained by liquid phase radical copolymerization of Ti^IV-containing monomers. For Part 51, see Ref. 1. Deceased. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1739–1743, September, 1999.     

Preparation and reactivity of metal-containing monomers

The radical-induced copolymerization ofmeso-tetraphenylporphyrin monomers with the vinyl group in a benzene or pyrrole ring and their copper and zinc complexes with styrene and methyl methacrylate was studied. Porphyrin comonomers decrease the overall polymerization rate and the number-average molecular weight of the products formed compared to the weight of polystyrene obtained under similar conditions. The main reasons for termination of chain growth by vinylporphyrins were revealed, and some quantitative parameters of these reactions were obtained. IR and electronic absorption spectra of porphyrin-containing copolymers are discussed. According to the ESR spectra, the copper-containing centers in the copolymers are fairly remote from each other, and the metal-containing polymeric systems are magnetically dilute.For Part 45. seeIzv. Akad. Nauk, Ser. Khim., 1995, 2404 [Russ. Chem. Bull., 1995,44, 1758 (Engl. Transl. .)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2922–2929, December, 1996.     

Preparation and reactivity of metal-containing monomers.

The thermal decomposition of Cu^II, Co^II, Ni^II, Mn^II, Fe^III, and Cr^III methacryloylacetonates has been compared with the thermal behavior of the corresponding acetylacetonates and poly (methacryioylacetonates). Dehydration and thermal polymerization of methacryioylacetonates occur at 110–160 °C. The results of the thermolysis conform with the Irving-Williams sequence for the stability of the complexes of bivalent transition metals. Thermal destruction of metallopolymers differs from that of low-molecular analogs. The temperature of complete decomposition of the compounds studied correlates with the number of electrons in the d-orbital of the metal.For part 35 seeRuss. Chem. Bull., 1993,42, 1972.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 43–47, January, 1994.     

Synthesis and reactivity of metal-containing monomers

Acid and neutral Co^II, Cu^II, Ni^II, Zn^II, Fe^II, and Fe^III maleates, fumarates, and itaconates were obtained and characterized. The methods for their synthesis were optimized, and the valence state and coordination of metals were studied. Co^II and Fe^II hydrogen maleates, Co^II maleate, and Co^II fumarate were examined by X-ray diffraction analysis. The ligands based on unsaturated dicarboxylic acids can be mono-, bi-, and tetradentate, which results in the formation of acid salts, chain and three-dimensional coordination polymers, whose double bond is not involved in the coordination. The strong antiferromagnetic exchange (μ_elf=1.41 and 0.34 μ_B at 290 and 80 K, respectively) was detected in Cu^II itaconate. Based on the data of Mössbauer spectroscopy, the partial reduction of Fe^III to Fe^II during the synthesis of Fe^III maleate was shown to occur: δFe=0.43 and 1.27 mm s^?1, ΔE _Q=0.57 and 3.13 mm s^?1 and Γ=0.37 and 0.28 mm s^?1 atT=298 K for Fe^III and Fe^II, respectively.     

Preparation and reactivity of metal-containing monomers. 23. Transition metal complexes of methacryloylacetone

The Cu(II), Ni(II), Co(II), Mn(II), Fe(III), and Cr(III) complexes of methacryloylacetone have been obtained. Magnetochemical, IR, and electronic spectroscopic studies have shown these to contain the copper ion in a square planar configuration, and the other metals in the octahedral configuration. The complexes have similar steric structures both in the crystal and in solution.Institute of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka. I. I. Mechnikov Odessa State University. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 694–699, March, 1992.     

Preparation and reactivity of metal-containing monomers

Polymethacryloylacetonates of some transition metals were obtained by free-radical polymerization of the corresponding metal-containing monomers and the main regularities of the process were studied. The complexation with a metal ion decreased the reactivity of the methacryloylacetone towards polymerization in the series Mn^II > Co^II > Ni^II > Cr^III, which is analogous to the electronegativity of these metals. Macrochelates thus obtained contain one equivalent of metal per monomer unit and their molecular weights are within 10000–18200. The structure of the coordination site was shown to be retained in the course of polymerization.For communication 34, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2060–2064, December, 1993.     

Preparation and reactivity of metal-containing monomers

Homo- and copolymerization of vanadium-containing monomers (VCM) have been studied. Radical homopolymerization of VCM is accompanied by some side reactions, such as monomer disproportionation, copolymerization with ligandin situ, cyclopolymerization, V⁵⁺V⁴⁺ reduction,etc. These reactions complicate the interpretation of the results obtained. The character of radical copolymerization of VCM with styrene or acrylonitrile is preferably radical complex. Catalytic properties of vanadium-containing homo- and copolymers (in combination with organoaluminum compounds as cocatalysts) in Ziegler-Natta ethylene polymerization have been studied. It has been shown that the products inherit the properties of immobilized polymer catalysts.For Part 39, seeIzv. Akad. Nauk, Ser. Khim., 1994, 1047 [Russ. Chem. Bull., 1994, 43, 983 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2139–2144, December, 1994.     

Preparation and reactivity of metal-containing monomers

Mono- and disubstituted cluster metal-containing monomers were obtained under mild conditions on interaction of Rh₆(CO)₁₆ with 4-vinylpyridine (4-ViPy) in the presence of N-trimethylaminoxide. These products were characterized by IR and¹H NMR spectroscopy and by elemental and X-ray analyses. Rh₆(CO)₁₅(4-ViPy) was found to be an octahedral cluster with eleven terminal and four ₃-bridging carbonyl ligands. 4-ViPy is linked with the Rh(3) atom through the N atom and occupies the coordination site of the twelfth CO terminal ligand. The mean value of the Rh-Rh bond length is 2.762 Å. The unsaturated ligand has little or no effect on the geometry of the starting cluster and its double bond retains the ability to undergo addition reactions.For part 28, seeRuss. Chem. Bull., 1993, 453.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 975–979, May, 1993.     

Preparation and reactivity of metal-containing monomers

Metal-containing monomers based on vinyl derivatives of heterocycles (4-vinylpyridine, 3,5-dimethyl-1-vinylpyrazole, 2-methyl-5-vinyltetrazole) and NiCl₂, CoCl₂, CrCl₃ have been prepared and characterized by chemical analysis, IR and electron spectroscopy. By means of spectral methods, the complex formation has been shown to involve N atom of the heterocycle, while the exocyclic C = C bond does not participate in the process. The structure of polyhedrons formed has been characterized both in the solid state and in methanol or DMF. The comparison of splitting parameters for different symmetries indicates that in passing from five-membered to six-membered vinylheterocycles, the strength of the ligand field is greatly enhanced.For part 24, seeIzv. Akad. Nauk, Ser. Khim., 1992, 2066 [Bull.Russ.Acad.Sci.Div.Chem.Sci., 1992,41, 1609].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 76–80, January, 1993.     

Preparation and reactivity of metal-containing monomers 19. Copolymerization of transition metal acrylates

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 352–357, February, 1991.     

Synthesis and reactivity of metal-containing monomers 64. Synthesis,structure, polymerization,and catalytic properties of the palladium and cobalt vinylporphyrin complexes

2-Vinylporphyrin and its complexes with Pd^II and Co^II were synthesized and characterized by NMR, IR, and mass spectra. The palladium vinylporphyrin complexes are efficient metal-containing monomers in radical copolymerization with styrene. Palladium(II) in an amount of up to 1 mol.% can thus be introduced into the polymers. The synthesized polymeric Pd complexes perform the photosynthesized activation of dioxygen to the lowest excited singlet state, which is an active oxidizing agent for anthracene producing the 1,4-addition products. The monomeric and macromolecular cobalt complexes are chain-transfer catalysts in radical styrene polymerization. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 152–158, January, 2007.     

Preparation and reactivity of metal-containing monomers. 21. Spontaneous polymerization of acrylamide coordinated to metal nitrates

Acrylamide coordinated to Cr(III), Bi(III), Pb(II), and Ca(II) nitrates polymerizes spontaneously in concentrated aqueous solutions at 20°C with formation of glass-like polymers containing water. The process takes from several hours to several days, depending on reaction conditions and the nature of the metal nitrate. The product contains water-soluble and water-insoluble fractions. The insoluble fraction is polyacrylamide containing no metal compound. The possibility of spontaneous copolymerization of acrylamide complexes of metal nitrates with other water-soluble monomers was established.Institute of Energy Problems in Chemical Physics, Chernogolovka Branch, Russian Academy of Sciences, 142432 Chernogolovka. Institute of Chemical Physics, Chernogolovka Branch, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2073–2080, September, 1992.     

Synthesis and reactivity of metal-containing monomers. Part 59. Preparation and polymerization transformations of vinyl and isopropenyl derivatives of hafnocene dichloride

Novel vinyl- and isopropenyl-substituted cyclopentadienyl complexes of hafnium(IV), [C₅H₄(CR=CH₂)]₂HfCl₂[R = H (5), CH₃ (6)], were prepared and characterized. The organometallic monomers obtained were shown to undergo radical or anionic homopolymerization. Copolymerization of these metallocenes with styrene was performed. The potential applications of the metal polymers in question were considered.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 242–246, January, 2005.     

Preparation and reactivity of metal-containing monomers. 16. Thermal polymerization characteristics of transition metal acrylamide complexes

The thermal polymerization of Mn(II), Co(II), Ni(II), and Zn(II) acrylamide nitrate complexes initiates spontaneously in the mp 80–100°C temperature range. Addition of a radical reaction inhibitor such as 2,2,4,4-tetramethyl-piperidine-1-oxide to these complexes shifts the polymerization range toward higher temperatures, while above certain concentrations of the additive, decomposition of the nitrate portion of the adducts takes place. A mechanism for the thermal polymerization of transition metal acrylamide nitrate complexes is proposed, involving initiation by the products of partial decomposition of the nitrate groups. A correlation or relationship has also been demonstrated between the thermal stability of these groups in the complexes and the ligand composition.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1015–1020, May, 1990.The authors thank V. A. Koroban' for helpful discussions of these results.