Reactivity of metal-containing monomers

Thermal conversion of cobalt(II) maleate, CoC₄H₂O₄2H₂O, (1) at 340–370 °C was studied. The composition of the products of pyrolysis was determined. The major solid-phase product of decomposition consists of nano-sized particles of CoO (sizes vary within narrow limits) stabilized by the polymeric matrix. Thermal conversions of Co^II maleate involve dehydration, polymerization of dehydrated monomers, and decarboxylation of the resulting polymer.     

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.     

Preparation and reactivity of metal-containing monomers

Modified polystyrene and polyacrylonitrile possessing cluster fragments in polymer chains have been obtained by radical copolymerization of styrene or acrylonitrile with triosmium carbonyl cluster complexes having double bonds capable of polymerization in their ligand surroundings. The thermal stability of the copolymers produced has been studied by DTG analysis. The temperature increase characteristic of both polymer and cluster pyrolysis has been observed for clusters containing polystyrene. The cluster complexes have been also shown to influence to a great extent the destruction of polyacrylonitrile, thus preventing the formation of stable fused structures in polymer chains.     

Preparation and reactivity of metal-containing monomers

We have observed the phenomenon of thermally initiated frontal polymerization of acrylamide complexes of nitrates of Mn(II), Co(II), Ni(II), and Zn(II). The velocity of propagation of the polymerization front when using different complexes is (2–9)·10^–2 cm/sec and decreases in the sequence of nitrates: Co(II) > Ni(II) > Mn(II) > Zn(II). Analogous complexes of Cu(II) and Fe(III) under the studied conditions are not polymerized. We have shown that the frontal polyerization products are three-dimensional polymers which are insoluble in organic solvents and slowly swell in water.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 768–772, April, 1990.We thank I. N. Ivlev for making the magnetic susceptibility measurements, and T. I. Ponomarev for studying the thermomechanical properties of the frontal polymerization products; and we acknowledge S. P. Davtyan for discussion of the results obtained.     

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

XPS and IR studies and elemental analysis of the polymerization product of Cu(II) acrylate suggest the partial reduction of Cu(II) during polymerization. A scheme of the polymer structure with metals of different valencies is suggested.For part 31 see Izv. Akad. Nauk, Ser. Khim., 1993, 1293 [Russ. Chem. Bull., 1993, 42, 1236 (Engl. Transl.)].Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1565–1568, September, 1993.     

Preparation and reactivity of metal-containing monomers

The stability constants of some bi- and trivalent metal complexes with methyl-, trifluoromethyl-, and phenyl-substituted 6-heptene-1,3-diones have been determined by pH-metric titration at 20 °C and an ionic strength = 0.1. It is proposed that vinyl groups of ligands are involved in complexation.For Part 44 seeIzv. Akad. Nauk, Ser. Khim., 1995, 1827 [Russ. Chem. Bull., 1995,44, 1758 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2404–2408, December, 1995.This work was partially financially supported by the International Science Foundation (Grant No. NJB000).     

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.     

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

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

Thermal transformations (at 340 to 390 °C) of coprecipitates of iron and cobalt acrylates, [Fe₃O(CH₂CHCOO)₆OH][Co(CH₂CHCOO)₂]_2.4 (1) and [Fe₃O(CH₂CHCOO)₆OH][Co(CH₂CHCOO)₂]_1.5·3H₂O (2), are studied. The dependence of the degree of gas evolution () on time is described by the equation () wherek ₁=2.3 · 10¹² · exp[–49500/(RT)] s^–1,k ₂=6.0 · 10⁶ · exp[–33000/(RT)] s^–1 andk ₁=2.6 · 10¹² · exp[–49000/(RT)] s^–1,k ₂=6.6 · 10⁵ · exp[–30000/(RT)] s^–1 for cocrystallizates1 and2, respectively. The coefficient ₁ decreases as the temperature increases. The value of ₁ for compound1 is higher than that for compound2. The composition of products of the transformations of1 and2 are studied. The main solid state products of the decomposition are nanometer-sized particles of cobalt ferrite, CoFe₂O₄, with a narrow size distribution stabilized by the polymeric matrix. The thermal transformations of cocrystallizates1 and2 include dehydration, thermal decomposition, copolymerization in the solid state, and decarboxylation of the metallocarboxylate groups of the polymer. The effect of the ratio between the Fe clusters and the Co-containing fragments on the process of thermal transformation is analyzed.For Part 40, seeRuss. Chem. Bull., 1994,43, 2020.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 885–893, May, 1995.The authors are grateful to A. N. Titkov for optical microscopic and electron microscopic studies.     

Preparation and reactivity of metal-containing monomers

The stability of chelates of several bivalent metals with poly(methacryloylacetone) was determined by pH titration. Two models in which the fragment of a polymeric molecule in the coordination sphere of a metal was approximated by either a mono- or a bidentate ligand were considered. Different mechanisms of complex formnation were realized depending on the nature of M(II).For part 29 seeIzv. Akad. Nauk, Ser. Khim., 1993, 975 [Russ. Chem. Bull., 1993,42, 937 (Eng.Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1063–1066, June, 1993.     

Preparation and reactivity of metal-containing monomers

Vinylporphyrins containing one vinyl group at the pyrrole or benzene ring and their complexes with Cu²⁺ and Zn²⁺ have been obtained by the Wittig reaction. Compounds obtained were characterized by physicochemical methods. X-ray diffraction analysis of 5-(4-vinylphenyl)-10,15,20-triphenylporphyrin has been carried out. It is likely that the inclusion of the vinyl group is accompanied by weak electron effects on the macrocycle. No nonequivalence of N-H bonds is observed in initial macrocycles.     

Preparation and reactivity of metal-containing monomers

Starting with the trinuclear clusters, M₃(CO)₁₂ (where M=Os or Ru), Os₃(CO)₁₁(NCCH₃), Os₃(CO)₁₀(NCCH₃)₂, and (-H)Os₃(-OR)(CO)₁₀ (where R=H or Ph), and polyfunctional organic compounds containing vinyl or allyl groups, a number of cluster monomeric complexes have been synthesized containing ligands with an uncoordinated C=C bond,viz.: (-H)Os₃(-4-Vpy)(CO)₁₀, (-H)Os₃(-O₂CCH=CH₂)(CO)₁₀, (-H)Os₃(-OCNHCH₂CH=CH₂)(CO)₁₀, and (-H)M₃(-SCH₂CH=CH₂)(CO)₁₀. The (-H)Os₃(-4-Vpy)(PPh₃)(CO)₉ complex was investigated by X-ray diffraction analysis.For part 30, seeRuss. Chem. Bull., 1993,42, 1016.Vpy is the vinylpyridine ligand.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1293–1298, July, 1993.     

Preparation and reactivity of metal-containing monomers

Russian Chemical Bulletin - The monomer [Cr3O(OCOCH=CH2)6]OH was produced by reaction of acrylic acid with fresh chromium hydroxide. This monomer was investigated by a number of physicochemical...     

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

The thermal decomposition of iron (III) acrylate, [Fe₃O(CH₂=CHCOO)₆ · 3H₂O]OH (FeAcr), a monomer with a complex cluster cation, has been studied at 200–370 °C. Thermal transformations of FeAcr occur in two temperature regions. The rates of gas evolution in the low temperature region (200–300 °C) and the high temperature region (300–370 °C) are described by first-order equations withk=4.2 · 10²¹exp[−59000/(RT)] s⁻¹ andk=1.3 · 10⁶exp[−30500/(RT)] s⁻¹, respectively. A study of the qualitative and quantitative composition of the products of FeAcr thermolysis was carried out. The thermal transformation of FeAcr is a complex process of dehydration, degradation, and polymerization in the solid phase followed by decarboxylation of the metal-carboxyl groups of the polymer. for part 33 see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1743–1750, October, 1993.     

Preparation and reactivity of metal-containing monomers

Electroreduction of methacryloylacetone and its Fe^III and Cu^II complexes was studied by cyclic voltammetry and preparative electrolysis on a Hg electrode. The possibility of the electropolymerization of the compounds at highly negative potentials (–2.0 V, vs sce) has been demonstrated. The polymers obtained were characterized by elemental analysis, electronic, IR-, and Mössbauer spectroscopy.For part 36, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 255–261, February, 1994.     

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.