New Heterocyclic Organophosphorus–Sulfur–Nitrogen Compounds,Syntheses and Structures

The new compound C₁₀H₆P(S)[NSi(CH₃)₃]₂P(S) ( 3 ) which contains a P₂N₂ heterocycle has been prepared in low yield by partial thermal decomposition of 1-{[N,N′-bis(trimethylsilyl)acetamidinium]sulfido}-3-(trimethylsilylamino)-1 H,3 H,1 λ⁵,3 λ⁵-naphtho[1,8 a,8-cd][1,2,6]thiadiphosphinine-1,3-dithione [CH₃C{NHSi(CH₃)₃}₂]⁺[C₁₀H₆P(S)(NHSiMe₃)SP(S)₂]^– ( 2 ). Reaction of 2 with potassium hydroxide in acetonitrile gives the completely desilylated product [CH₃C(NH₂)₂]⁺[C₁₀H₆P(S)(NH₂)SP(S)₂]^– ( 4 ). The structures of the new compounds 3 and 4 were elucidated by FTIR and NMR spectroscopy methods and by X-ray structure analyses.     

Multifunctional coupling agents for living cationic polymerization. IV. Synthesis of end-functionalized multiarmed poly(vinyl ethers) with multifunctional silyl enol ethers

Telechelic ( 8 ) and end-functionalized four-arm star polymers ( 9 ) were synthesized through the coupling reactions of end-functionalized living poly(isobutyl vinyl ether) ( 5; DP _n ～ 10) with the bi-and tetrafunctional silyl enol ethers, H_4-nC? [CH₂OC₆H₄C(OSiMe₃) = CH₂]_n ( 3: n = 2; 4: n = 4). The precursor polymers 5 were prepared by living cationic polymerization with functionalized initiators, CH₃CH(Cl)OCH₂CH₂X(6), in conjunction with zinc chloride in methylene chloride at ?15°C. The initiators 6 were obtained by the addition of hydrogen chloride gas to vinyl ethers bearing pendant functional groups X , including acetoxy [? OC(O)CH₃], styryl (? OCH₂C₆H₄-p-CH = CH₂), and methacryloyl [? OC(O)C(CH₃) = CH₂]. The coupling reactions with 3 and 4 in methylene chloride at ?15°C for 24 h afforded the end-functionalized multiarmed polymers ( 8 and 9 ) in high yield (>91%), where those with styryl or methacryloyl groups are new multifunctional macromonomers. © 1994 John Wiley & Sons, Inc.     

Oxidative addition of different electrophiles with rhodium(I) carbonyl complexes of unsymmetrical phosphine–phosphine monoselenide ligands

Dimeric chlorobridge complex [Rh(CO)₂Cl]₂ reacts with two equivalents of a series of unsymmetrical phosphine–phosphine monoselenide ligands, Ph₂P(CH₂)_nP(Se)Ph₂ {n = 1( a ), 2( b ), 3( c ), 4( d )}to form chelate complex [Rh(CO)Cl(P∩Se)] ( 1a ) {P∩Se = η²‐(P,Se) coordinated} and non‐chelate complexes [Rh(CO)₂Cl(P～Se)] ( 1b–d ) {P～Se = η¹‐(P) coordinated}. The complexes 1 undergo oxidative addition reactions with different electrophiles such as CH₃I, C₂H₅I, C₆H₅CH₂Cl and I₂ to produce Rh(III) complexes of the type [Rh(COR)ClX(P∩Se)] {where R = ? C₂H₅ ( 2a ), X = I; R = ? CH₂C₆H₅ ( 3a ), X = Cl}, [Rh(CO)ClI₂(P∩Se)] ( 4a ), [Rh(CO)(COCH₃)ClI(P～Se)] ( 5b–d ), [Rh(CO)(COH₅)ClI‐(P～Se)] ( 6b–d ), [Rh(CO)(COCH₂C₆H₅)Cl₂(P～Se)] ( 7b–d ) and [Rh(CO)ClI₂(P～Se)] ( 8b–d ). The kinetic study of the oxidative addition (OA) reactions of the complexes 1 with CH₃I and C₂H₅I reveals a single stage kinetics. The rate of OA of the complexes varies with the length of the ligand backbone and follows the order 1a > 1b > 1c > 1d . The CH₃I reacts with the different complexes at a rate 10–100 times faster than the C₂H₅I. The catalytic activity of complexes 1b–d for carbonylation of methanol is evaluated and a higher turnover number (TON) is obtained compared with that of the well‐known commercial species [Rh(CO)₂I₂]^?. Copyright © 2006 John Wiley & Sons, Ltd.     

Palladium Chemistry Related to Benzyl Bromide Carbonylation: Mechanistic Studies

Summary.  Palladium(II) complexes of the general formula PdCl₂ (PR₃)₂ with PR₃ = { P(OPh)₃}, P(O-4-MeC₆H₄)₃, P(O-2-MeC₆H₄)₃, and PPh₂(OBu) were reduced by NEt₃ in chloroform or benzene to Pd(0) complexes Pd(PR₃)₄ and Pd(PR₃)_x(NEt₃) _4−x . The same reaction performed in the presence of air gave CH₃CHO or CH₃CH₂CHO when NPr₃ was used instead of NEt₃. Pd(P(OPh)₃)₄ reacted with benzyl bromide affording the oxidative addition product cis-PdBr(CH₂Ph)(P(OPh)₃)₂. The reaction of PdCl₂(P(OPh)₃)₂ with benzyl bromide was observed only in the presence of NEt₃, and a dimeric complex of [PdBr(CH₂Ph)(P(OPh)₃)]₂ was identified as the reaction product. Both benzyl complexes reacted fast with CO (1 atm) to form acyl complexes exhibiting ν(CO) bands at 1709 and 1650 cm⁻¹.     

Optisch aktive übergangsmetall-komplexe LXIV. Neue optisch aktive Cp(CO)Fe-acyl-komplexe mit

The novel complexes CpFe(CO)(COR)P(C₆H₅)₂NR'R^* with Cp = C₅H₅,C₉H₇ (indenyl); R = CH₃, C₂H₅, CH(CH₃)₂, CH₂C₆H₅;R` = H, CH<sub>3</sub>, C<sub>2</sub>H<sub>5</sub>, CH<sub>2</sub>C<sub>6</sub>H<sub>5</sub> and R<sup>*</sup> = (S)-CH(CH<sub>3</sub>)(C<sub>6</sub>H<sub>5</sub>), have been synthesized by reaction of CpFe(CO)<sub>2</sub>R wiht P(C<sub>6</sub>H<sub>5</sub>)<sub>2</sub>NR`R^* and characterized analytically as well as spectroscopically. The pairs of diastereoisomers RS/SS have been separated by preparative liquid chromatography and fractional crystallization, respectively. The optically pure complexes (+)₄₃₆- und ()₄₃₆-CpFe(CO)(COR)P(C₆H₅)₂NR`R^* are configurationally stable at room temperature. At higher temperatures they equilibrate with CpFe(CO)₂R and epimerize with respect to the Fe configuration.     

Palladium Chemistry Related to Benzyl Bromide Carbonylation: Mechanistic Studies

 Palladium(II) complexes of the general formula PdCl₂ (PR₃)₂ with PR₃ = { P(OPh)₃}, P(O-4-MeC₆H₄)₃, P(O-2-MeC₆H₄)₃, and PPh₂(OBu) were reduced by NEt₃ in chloroform or benzene to Pd(0) complexes Pd(PR₃)₄ and Pd(PR₃)_x(NEt₃) _4−x . The same reaction performed in the presence of air gave CH₃CHO or CH₃CH₂CHO when NPr₃ was used instead of NEt₃. Pd(P(OPh)₃)₄ reacted with benzyl bromide affording the oxidative addition product cis-PdBr(CH₂Ph)(P(OPh)₃)₂. The reaction of PdCl₂(P(OPh)₃)₂ with benzyl bromide was observed only in the presence of NEt₃, and a dimeric complex of [PdBr(CH₂Ph)(P(OPh)₃)]₂ was identified as the reaction product. Both benzyl complexes reacted fast with CO (1 atm) to form acyl complexes exhibiting ν(CO) bands at 1709 and 1650 cm⁻¹.     

EHT Model Studies on Coordination-Sphere Effects in the Elementary steps of d0 transition-metal-catalyzed Ziegler-Natta polymerization

In a theoretical investigation on Ziegler-Natta catalysis, the influence of the coordination number and ligand type of model compounds in relevant reaction steps were studied. Thus, by using the MEHT method, insertion reactions of ethylene into Zr–CH₃ and Zr–H bonds were analyzed in systems of the type [Zr(C₂H₄)R₄R′]^?[Zr(Cp)(C₂H₄)R₂R′], and [Zr(Cp)(C₂H₄)R₃R′]^?(R=R′=CH₃, R=CH₃, R′=H). It was found that all processes do not have significant kinetic barriers, whereas the reverse reactions in particular the β-hydride elimination have relatively high ones. The influence of coordination geometry and number on these transformations was found to be insignificant. While studying related conversions starting from [Zr(L)(C₂H₄)R₃R′], [Zr(Cp)(C₂H₄)RR′(L)]⁺, and [Zr(Cp)(C₂H₄)R₂R′(L)] (L = π-donor, R=R′=CH₃ or R=CH₃, R′=H) compounds a pronounced π-donor effect was observed. Methyl insertions in these cases showed a higher computed activation barrier than hydride migrations. An orbital basis for this phenomenon was provided and conclusions concerning chain-length control in Ziegler-Natta catalysis were drawn.     

Transition metal derivatives of arenediazonium ions: XIV. Reactions of arenediazomolybdenum(II) complexes with neutral and anionic Lewis bases

The reactions of arenediazomolybdenum(II) complexes such as [(η-C₅H₅)Mo(N₂C₆H₄CH₃-p)I₂]₂, (η-C₅H₅)Mo(CO species with neutral and anionic monodentate or chelating ligands have been investigated. The new arenediazo complexes isolated from these reactions include neutral species such as (η-C₅H₅)Mo(PPh₃)(N₂C₆H₄CH₃-p)I₂ and (η-C₅H₅)Mo(N₂C₆H₄CH₃-p) cations of the type [η-C₅H₅)Mo(bipy)(N₂C₆H₄CH₃-p)I]⁺ and the anion [(η-C₅H₅)Mo(N₂C₆H₄CH₃-p)I₃]^?. The structures of the new complexes are discussed.     

Synthesis and helicity of optically active poly(N‐propargylphosphonamidates) having chiral phosphorus center

Novel chiral N‐propargylphosphonamidate monomers (HC?CCH₂NHP(?O)R? O? menthyl, 1 : R = CH₃, 2 : R = C₂H₅, 3 : R = n‐C₃H₇, 4 : R = Ph) were synthesized by the reaction of the corresponding phosphonic dichlorides with menthol and propargylamine. Pairs of diastereomeric monomers 1 – 4 with different ratios were obtained due to the chiral P‐center and menthyl group. One diastereomer could be separated from another one in the cases of monomers 1 and 2 . Polymerization of 1 – 4 with (nbd)Rh⁺[η⁶‐C₆H₅B^?(C₆H₅)₃] as a catalyst in CHCl₃ gave the polymers with number‐average molecular weights ranging from 5000 to 12,000 in 65–85%. Poly( 1 )–poly( 4 ) exhibited quantitative cis contents, and much larger specific rotations than 1 – 4 did in CHCl₃. The polymers showed an intense Cotton effect around 325 nm based on the conjugated polyacetylene backbone. It was indicated that the polymers took a helical structure with predominantly one‐handed screw sense, and intramolecular hydrogen bonding between P?O and N? H of the polymers contributed to the stability of the helical structure. Poly( 1a ) and poly( 2a ) decreased the CD intensity upon raising CH₃OH content in CHCl₃/CH₃OH. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1515–1524, 2007     

2J(P,C) and 3J(P,C) Coupling Constants in Some New Phosphoramidates. Crystal Structures of CF3C(O)N(H)P(O)[N(CH3)(CH2C6H5)]2 and 4‐NO2‐C6H4N(H)P(O)[4‐CH3‐NC5H9]2

Some new phosphoramidates were synthesized and characterized by ¹H, ¹³C, ³¹P NMR, IR spectroscopy and elemental analysis. The structures of CF₃C(O)N(H)P(O)[N(CH₃)(CH₂C₆H₅)]₂ ( 1 ) and 4‐NO₂‐C₆H₄N(H)P(O)[4‐CH₃‐NC₅H₉]₂ ( 6 ) were confirmed by X‐ray single crystal determination. Compound 1 forms a centrosymmetric dimer and compound 6 forms a polymeric zigzag chain, both via ‐N‐H…O=P‐ intermolecular hydrogen bonds. Also, weak C‐H…F and C‐H…O hydrogen bonds were observed in compounds 1 and 6 , respectively. ¹³C NMR spectra were used for study of ²J(P,C) and ³J(P,C) coupling constants that were showed in the molecules containing N(C₂H₅)₂ and N(C₂H₅)(CH₂C₆H₅) moieties, ²J(P,C)>³J(P,C). A contrast result was obtained for the compounds involving a five‐membered ring aliphatic amine group, NC₄H₈. ²J(P,C) for N(C₂H₅)₂ moiety and in NC₄H₈ are nearly the same, but ³J(P, C) values are larger than those in molecules with a pyrrolidinyl ring. This comparison was done for compounds with six and seven‐membered ring amine groups. In compounds with formula XP(O)[N(CH₂R)(CH₂C₆H₅)]₂, ²J(P,CH₂)_benzylic>²J(P,CH₂)_aliphatic, in an agreement with our previous study.     

Mass spectra of some neopentylphosphorus derivatives

The fragmentation patterns and major metastable ions of the mass spectra of the neopentyl-phosphorus derivatives [(CH₃)₃CCH₂]₃P, [(CH₃)₃CCH₂]₂P(O)H, [(CH₃)₃CCH₂]_nPX_3-n (n = 1 and 2; X = H, Cl, C₆H₅ and CH = CH₂), [(CH₃)₃CCH₂]₃PS, [(CH₃)₃CCH₂]_nP(S)R_3-n (n = 1 and 2; R = C₆H₅ and CH = CH₂), [(CH₃)₃ CCH₂]₂PCH₂CH₂P[CH₂C(CH₃)₃]₂, ([CH₃)₃CCH₂]₂PCH₂PCH₂-CH₂P(H)C₆H₅ and [(CH₃)₃CCH₂]₂PCH₂CH₂P(S)(CH₃)₂ are described. Fragmentation of a neopentyl group by elimination of either C₄H₈ or CH₃ is very favourable when the neopentyl group is bonded to either a tricoordinate or tetracoordinate phosphorus atom. In neopentylphosphines with two or three neopentyl groups, stepwise elimination of C₄H₈ from all of the neopentyl groups occurs very readily. The resulting [(CH₃)_nPX]^+._3-n ions are often the most intense ions in the mass spectra.     

Synthesis and reactivity of rhodium(I) complexes of the type Rh(L-L)(CO)[P(OPh)3] and Rh(L-L)[P(OPh)3]2

Summary The carbonyl ligands in the Rh¹ complexes Rh(L-L)(CO)₂ [L-L=anthranilate (AA) orN-phenylanthranilate(FA) ions] are replaced by P(OPh)₃ to form the mono-or disubstituted products, Rh(L-L)(CO)[P(OPh)₃] and Rh(L-L)[P(OPh)₃]₂ respectively depending on the [P(OPh)₃]/[Rh] molar ratio, at room temperature and in air. Under argon at [P(OPh)₃]/[Rh]4 theortho-metallated Rh¹ complex Rh[P(OPh)₃]₃[P(OC₆H₄)-OPh)₂] is formed. The new route forortho-metallated Rh¹ complex synthesis is described.The Rh(AA)(CO)₂ complex was used as a catalyst precursor in hydroformylation of olefins.     

13C n.m.r. spectroscopy of diethyl alkyl- and benzyl-phosphonates. A study of phosphorus–carbon spin–spin coupling constants over one to seven bonds

¹³C chemical shifts and ³¹P? ¹³C spin–spin coupling constants are reported for 10 alkyl-, 20 benzyl- and 3 (naphthylmethyl)-phosphonates. While in saturated aliphatic chains P–C couplings over more than four bonds cannot be resolved, couplings over up to seven bonds are observed in the benzyl type systems. Conformational and substituent effects on J(PC) are studied and discussed. ⁿJ(PF) (n = 4, 5, 6) are reported for the isomeric (fluorobenzyl)phosphonates and ⁿJ(PP) (n = 5, 6, 7) were obtained from the ¹³C satellites in the ³¹P n.m.r. spectra of the isomeric diphosphonates, C₆H₄[CH₂P(O)(OEt)₂]₂. Comparison of those ¹³C absorptions of the latter, which represent the X parts of ABX or AA′X spin systems, with the spectra of the corresponding (methylbenzyl)phosphonates, CH₃C₆H₄CH₂P(O)(OEt)₂, yielded the relative signs of ⁿJ(PC) (n = 2–6).     

Organophosphazenes 27: the Synthesis and Polymerization of (4- Ethenylphenyl)Pentafluorocyclotriphosphazene

Abstract

The synthesis and homopolymerization of a fluorocyclotriphosphosphazene with a directly bonded styrene moiety is presented. A multistep sequence was employed wherein commercially available p-bromostyrene is first converted to 1-(4-bromophenyl)-1-methoxyethene, 4-BrC₆H₄C(OCH₃)CH₂ which in turn is lithiated and added to N₃P₃F₆ to give (4-(1-methoxyethenyl)phenyl)pentafluorocyclotri phosphazene, N₃P₃F₅(4-C₆H₄C(OCH₃)?CH₂)(2). Addition of tri(n-butyl)tin hydride to 2 followed by elimination of tri(n-butyl)tin methoxide over silica produced the target monomer, (4-ethenylphenyl)- pentafluorocyclotriphosphazene, and N₃P₃F₅(4-C₆H₄CH?CH₂)(3). The new phosphazene derivatives were characterized by mass spectrometry, NMR (¹H,¹³C,¹⁹F,³¹P) and IR spectroscopy. Radical addition polymerization of 3 resulted in the formation of poly(p-pentafluorocyclotriphosphazenylstyrene)(4). Molecular weights of the new polymer were determined by GPC and membrane osmometry. The GPC data suggested the occurrence of chain transfer in the polymerization. TGA studies showed that 4 exhibits high thermal stability compared to other organophosphazene polymers. The T_g value is significantly greater than that of polystyrene.     

Synthesis and characterization of aluminum(III) and tin(II) complexes supported by diiminophosphinate ligands and their application in ring‐opening polymerization catalysis of ε‐caprolactone

A series of Al(III) and Sn(II) diiminophosphinate complexes have been synthesized. Reaction of Ph(ArCH₂)P(?NBu^t)NHBu^t (Ar = Ph, 3 ; Ar = 8‐quinolyl, 4 ) with AlR₃ (R = Me, Et) gave aluminum complexes [R₂Al{(NBu^t)₂P(Ph)(CH₂Ar)}] (R = Me, Ar = Ph, 5 ; R = Me, Ar = 8‐quinolyl, 6 ; R = Et, Ar = Ph, 7 ; R = Et, Ar = quinolyl, 8 ). Lithiated 3 and 4 were treated with SnCl₂ to afford tin(II) complexes [ClSn{(NBu^t)₂P(Ph)(CH₂Ar)}] (Ar = Ph, 9 ; Ar = 8‐quinolyl, 10 ). Complex 9 was converted to [(Me₃Si)₂NSn{(NBu^t)₂P(Ph)(CH₂Ph)}] ( 11 ) by treatment with LiN(SiMe₃)₂. Complex 11 was also obtained by reaction of 3 with [Sn{N(SiMe₃)₂}₂]. Complex 9 reacted with [LiOC₆H₄Bu^t‐4] to yield [4‐Bu^tC₆H₄OSn{(NBu^t)₂P(Ph)(CH₂Ph)}] ( 12 ). Compounds 3–12 were characterized by NMR spectroscopy and elemental analysis. The structures of complexes 6 , 10 , and 11 were further characterized by single crystal X‐ray diffraction techniques. The catalytic activity of complexes 5–8 , 11 , and 12 toward the ring‐opening polymerization of ε‐caprolactone (CL) was studied. In the presence of BzOH, the complexes catalyzed the ring‐opening polymerization of ε‐CL in the activity order of 5 > 7 ≈ 8 > 6 ? 11 > 12 , giving polymers with narrow molecular weight distributions. The kinetic studies showed a first‐order dependency on the monomer concentration in each case. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4621–4631, 2006     

Fluorescent Properties of Three Carboxyarylphosphonate Polymers with Unusual Polynuclear Zinc(II) Units

Three novel carboxyarylphosphonate polymers {[Zn₂(PCP)(H₂PCP)(phen)₂] · H₂O}_n ( 1 ), [Zn(HPCP)(4,4′‐bipy)]_n ( 2 ), and [Zn₃(MCP)₂(2,2′‐bipy)]_n ( 3 ) [PCP^3– = p‐O₂C(C₆H₄)CH₂PO₃^3–, MCP^3– = m‐O₂C(C₆H₄)CH₂PO₃^3– and phen = phenanthroline] were synthesized and characterized by single‐crystal X‐ray diffraction. Compound 1 features a butterfly‐shaped dimer consisting of [Zn₄P₄O₁₀] tetranuclear units, which are further linked by hydrogen bonds and π–π stacking interactions into a 3D supramolecular framework. In 2 , there is an infinite P–O–Zn inorganic 2D (4,4) layer with the phosphonate moieties of HPCP^2– and unidentate 4,4′‐bipy ligands vertically sticking out. As for 3 , the novel [Zn₆P₄O₁₂] hexanuclear units with “chair“ conformation are tetrahedrally bridged by eight MCP^3– to generate a 2D double‐layer, in which the windows are occupied by 2,2′‐bipy molecules. Additionally, 2D correlation analysis of FTIR with thermal perturbation of 3 were discussed. Compounds 1 – 3 exhibit intense solid state fluorescent emissions. Thermogravimetric analyses suggested the very high stability.     

Organotin(IV) complexes of dibasic tridentate Schiff bases containing ONO donor atoms

Organotin(IV) Schiff base complexes of the type (L)SnR₂ [where R?CH₃, C₆H₅ or CH₂CH₂CO₂ CH₃], (LH)Sn(C₆H₅)₃ and (L)SnCl(CH₂CH₂CO₂ CH₃) [where LH₂?2-N-salicylideneimino-2-methyl-1-propanol, derived from the condensation of salicylaldehyde and 2-amino-2-methyl-1-propanol] have been prepared and characterized on the basis of their elemental analyses, IR, ¹H, ¹³C and ¹¹⁹Sn NMR studies. In these mononuclear complexes the Schiff base acts either as a dianionic tridentate or as a monobasic bidentate moiety by coordinating through an alkoxy group, an azomethine nitrogen and a phenoxide ion to tin. Sulphur dioxide inserts in the tin–methyl/–phenyl bond in the above Schiff base complexes to give tin–O–sulphinates of formulae (L)RSn(SO₂R) and (LH)(C₆H₅)₂Sn(SO₂C₆H₅).     

Synthesis,characterization, and molecular structures of Ni(II) and Cd(II) complexes derived from dithiophosphonate

Two novel dithiophosphonate ligands, HS₂P(p‐C₆H₄OMe)(OCH₂CH₂CH(CH₃)₂) ( 1 ) and HS₂P(p‐C₆H₄OMe)(OCH(CH₃)₂) ( 2 ), were synthesized and characterized by multinuclear (¹H, ³¹P, and ¹³C) NMR, infrared spectroscopy as well as elemental analysis. The reactions of 1 and 2 with NiCl₂·6H₂O and Cd(NO₃)₂·4H₂O in methanol led to novel complexes 3 and 4 . The single crystal X‐ray structures of 3 and 4 showed tetracoordinated structure with square planar geometry for the nickel complex, while it showed pentacoordinated structure with distorted square‐pyramid environment for the cadmium complex.     

Novel Copolymers of Styrene. 3. Some Ring-Substituted Butyl 2-Cyano-3-Phenyl-2-Propenoates

Novel trisubstituted ethylenes, ring-substituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO₂C₄H₉ (where R is 2-C₆H₅CH₂O, 3-C₆H₅CH₂O, 4-C₆H₅CH₂O, 4-CH₃COO, 3-CH₃CO, 4-CH₃CO, 4-CH₃CONH, 2-CN, 3-CN, 4-CN, 4-(CH₃)₂N, 4-(C₂H₅)₂N) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and butyl cyanoacetate, and characterized by CHN analysis, IR, ¹H and ¹³C-NMR. All the ethylenes were copolymerized with styrene (M₁) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, ¹H and ¹³C-NMR. The order of relative reactivity (1/r₁) for the monomers is 4-C₆H₅CH₂O (6.39) > 2-C₆H₅CH₂O (2.06) > 3-CH₃CO (1.86) > 3-C₆H₅CH₂O (1.78) > 4-CH₃COO (1.58) > 3-CN (1.47) > 4-CN (1.21) > 4-(C₂H₅)₂N (1.19) > 4-(CH₃)₂N (1.18) > 2-CN (1.04) > 4-CH₃CO (0.71) > 4-CH₃CONH (0.63). Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (3.6–9.5% wt), which then decomposed in the 500–800°C range.     

Polymerization of cyclic esters of phosphoric acid. VI. Poly(alkyl ethylene phosphates). Polymerization of 2-alkoxy-2-oxo-1,3,2-dioxaphospholans and structure of polymers

Five-membered cyclic esters of phosphoric acid of the general formula: ? CH₂CH(R)OP(O)-(OR′)O? polymerize readily to solid, soluble polymers of high molecular weight without any rearrangement known for various tri- and pentavalent organophosphorus monomers. ¹H-, ¹³C-, and ³¹P-NMR spectra of polymers confirmed their linear structure: where R is H, with R′ = CH₃, C₂H₅, n-C₃H₇, i-C₃H₇; n-C₄H₉, CCl₃CH₂, or C₆H₅, or R is CH₂Cl and R′ is C₂H₅. The use of n-C₄H₉Li, (C₅H₅)₂Mg, or (i-C₄H₉)₃Al as initiators leads to polymers with M _n = 10⁴–10⁵.