Zur Heck-Reaktion von 1-Chloralk-1-inen – Synthese und Charakterisierung von 1,3-disubstituierten 7-(Prop-2-inyliden)bicyclo[2.2.1]heptanen und anderen Bicyclen

The Heck reaction of cyclohexene with 1-chloroalk-1-ynes ClC≡CR 1 (R = Ph a , c-Hex b , n-Bu c , n-Oct d ) using [Pd(OAc)₂]/NaO₂CH/[NEt₃Bz]Cl as catalyst system (DMF, 25 °C) affords 1,3-disubstituted 7-(prop-2-ynylidene)bicyclo[2.2.1]heptanes 2 as tandem products by reaction of cyclohexene and ClC≡CR in a ratio of 1:2. To a smaller extent, substituted 7-[(cyclohexenyl)methylidene]bicyclo-[2.2.1]heptanes 3 (tandem products by reaction of cyclohexene and ClC≡CR in a ratio of 2:1) and the regular Heck products (alkynylcyclohexenes 4 ) are formed. The homocoupling of 1 to give RC≡C–C≡CR does not take place, except for R = n-Oct where it proceeds as side reaction. The analogous reaction of ClC≡CR with cycloheptene affords the 2:1 products (substitued 8-[(cycloheptenyl)methylidene]biyclo[3.2.1]octanes 6 ) as main products and the 1:2 products (1,3-disubstituted 7-(prop-2-ynylidene)bicyclo[3.2.1]-octanes 5 ) as well as the regular Heck products (alkynylcycloheptenes 7 ) as side products. The ratio 5 : 6 is strongly influenced by the ratio cycloheptene : 1 . The products 2 , 5a and 6 were isolated and characterized by means of ¹H and ¹³C NMR spectroscopy. The molecular structures of 7-(1,3-diphenylprop-2-ynylidene)bicyclo[2.2.1]heptane ( 2a ) and 8-[(cyclo-heptenyl)phenylmethylidene)]bicyclo[3.2.1]octane ( 6a ) (as mixture of the cyclohept-3- and -4-enyl double bond isomers) were determined by single-crystal X-ray structure analysis.     

Determination of the tacticity of ring-opened metathesis polymers of norbornene and norbornadiene by 13C NMR spectroscopy of their hydrogenated derivatives

The 125 MHz ¹³C nuclear magnetic resonance (NMR) spectra of the hydrogenated derivatives of ring-opened metathesis polymers (ROMP) of bicyclo[2.2.1]hept-2-ene (norbornene) and bicyclo[2.2.1]hepta-2,5-diene (norbornadiene) prepared using a range of initiators, have been analysed in detail. The signals due to the methylene carbon atoms in the enchained cyclopentyl rings of these polymers show fine structure which is assigned to m and r ring dyads and mm, mr/rm and rr ring triads, enabling the tacticity of the hydrogenated polymer, and thus of the polyolefin precursor, to be determined for high-cis or high-trans polymers. Novel methods for making high-cis polymers are described and solvent-dependent variations in the stereospecificity of the propagation reaction have been observed.     

Amphiphilic macromolecular nanostructure materials derived from 5-(octanoate methyl)bicyclo[2.2.1]hept-2-ene and 5-(phthalimide methyl)bicyclo[2.2.1]hept-2-ene via ring-opening metathesis copolymerization

Novel highly stable polynorbornenes with self-assembling amphiphilic architecture containing hydrophilic ammonium salt and hydrophobic alkyl ester group were obtained via ring-opening metathesis polymerization (ROMP) of 5-(octanoate methyl)bicyclo[2.2.1]hept-2-ene (NBMO) and 5-(phthalimide methyl)bicyclo[2.2.1]hept-2-ene (NBMPI), hydrogenation, hydrazinolysis, and subsequent quaternization. Polymeric micelles of such amphiphilic random and block polynorbornenes formed in solvents by varying the content of ammonium salts were investigated. Amphiphilic block copolymers exhibited perfect spherical morphology. Nanoscale polymeric micelles of random copolymers with 50-75 mol% of ammonium salts were roughly spherical in shape, while the morphologies of micelles transferred into network-like aggregates as hydrophilic contents of the random copolymers are higher than 80 mol%. The formation and fine structures of micelles were investigated by dynamic light scattering (DLS), TEM, and fluorescence technique using pyrene as fluorescence probe.     

Silicon and Chlorine Substituted Unsaturated Polymers: ROMP of (bicyclo[2,2,1]hept-5-en-2-yl)ethylchlorodimethylsilane via Mo-based catalyst

Ring opening metathesis polymerization (ROMP) of a norbornene derivative that contains silicon and chlorine, (bicyclo[2,2,1]hept-5-en-2-yl)ethylchlorodimethylsilane, by using electrochemically produced active catalyst species (MoCl₅–e⁻–Al–CH₂Cl₂) was investigated. Silicon and chlorine containing unsaturated polymer was characterized by ¹H, ¹³C, and ²⁹Si-NMR and FTIR spectroscopy. The thermal behavior of the polymer was determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).     

Molecular architecture effect on reactivity of polynorbornenes with pendant α,β-unsaturated amide or ester bridged chains via ring-opening metathesis polymerization

The molecular architecture effect on active structure of miscellaneous polynorbornenes (Scheme 1) was investigated with pendant α,β-unsaturated amide or ester groups via ring-opening metathesis polymerization (ROMP). Remarkable differences in the reactivity and polymerization behavior of active norbornenes depend on various molecular architectures. Polynorbornenes derived from active norbornenes with ethylene between urethane group and ester group such as 3a,b (Scheme 1) showed excellent solubility. Organo-insoluble precipitate was obtained after ROMP of 5c with the amide group. Random copolymerization technique of bicyclo[2.2.1]hept-2-ene (NB) and 5c with amide group was considered to be a strategy to overcome the formation of precipitates, which expected to decrease the hydrogen bonding between two amide groups. High performance polynorbornenes with active groups could be designed with high potential of application for photoresist, UV curing and elastomers. Functional poly(5b) was incorporated into poly(methyl methacylate) [poly(MMA)] to produce AB cross-linked materials. The AB cross-linked material [15 wt% poly(5b), T_d10=355 °C in nitrogen] had higher thermal stability than pure poly(MMA) (T_d10=250 °C in nitrogen).     

聚丙烯成核剂双环[2.2.1]-庚烷-2,3-二羧酸钠的合成

以降冰片烯二酸酐为起始原料, 经水解中和和催化加氢制备了双环[2.2.1]-庚烷-2,3-二羧酸钠。通过研究催化加氢步骤中催化剂种类、催化剂用量、反应温度和反应压力等关键因素对双环[2.2.1]-庚烷-2,3-二羧酸钠的收率和纯度的影响, 获得了适宜的反应条件。实验结果表明:催化剂雷尼镍可代替文献报道的价格昂贵的钯/炭催化剂完成催化加氢反应, 在反应温度为60℃、反应压力为5MPa的条件下进行催化加氢, 双环[2.2.1]-庚烷-2,3-二羧酸钠的收率大于95%;红外光谱及核磁共振分析表明, 所得加氢产物与双环[2.2.1]-庚烷-2,3-二羧酸钠结构特征吻合。     

Metathesis ring opening polymerization of 5,6-dimethylenebicyclo[2.2.1]hept-2-ene

5,6-Dimethylenebicyclo[2.2.1]hept-2-ene ( I ) polymerizes in the presence of the two-component ring opening metathesis polymerization (ROMP) initiators WCl₆/(CH₃)4Sn and MoCl₅/(CH₃)4Sn. The product polymers were insoluble in all of many solvents investigated and are presumably cross-linked. The product polymers were investigated by IR and solid state ¹³C NMR spectroscopy, which established that the material consisted predominantly of poly(1,4-(2,3-dimethylene-cyclopentylene)vinylene) ( II ). A possible alternative route to II via thermal dehydrochlorination of poly(1,4-(2,3-bis(chloromethyl)cyclopentylene) vinylene) ( IV ) was also examined.     

Synthesis and characterization of poly[(2-dimethylsilyl-2-cyclopentene-1,4-diyl) vinylene]

Summary Ring opening metathesis polymerization (ROMP) of 2-dimethylsilylbicyclo[2.2.1]hept-2,5-diene (I) cocatalyzed by tungsten hexachloride/terramethyltin yields poly[(2-dimethyl-silyl-2-cyclopentene-1,4-diyl) vinylene] (II). This is the first example of ROMP of a monomer which contains a reactive Si-H bond. ¹H, ¹³C, ²⁹Si and IR spectroscopy were utilized to characterize II. The molecular weight distribution of II has been determined by gel permeation chromatography (GPC), its thermal stability by thermogravimetric analysis (TGA) and its glass transition temperature (Tg) by differential scanning calorimetry (DSC).     

The ROMP catalysts Mo(CO)5PPh3/alkylaluminum with unstrained cyclic and linear dienes as initiators of the addition polymerisation

Summary We study the polymerisation of a series of unstrained cyclic and acyclic dienes with the catalytic system of Mo(CO)₅PPh₃/alkylaluminum. The Mo(CO)₅PPh₃/alkylaluminum catalyse the nonmetathesis polymerisation, through a pair of ionic complexes similar to that of Ziegler-Natta mechanism, and not through the ROMP (Ring-Opening-Metathesis-Polymerisation) mechanism followed by strained olefins. Because of the nature of these complexes the reactivity is lower with respect to that of a common Ziegler-Natta catalyst, such as Cp₂TiCl₂/Et₃Al₂Cl₃, as it is demonstrated, by means of kinetics and ESR measurements, in the case of the polymerisation of of 1,5-cyclooctadiene. Similarly to the Ziegler-Natta catalysts, they give cyclised products in the polymerisation of 1,5-hexadiene and 1,7-octadiene, and the 1,4-cis unit in the case of the polypentadienes. Finally we find that they are active catalysts for the polymerisation of styrene. Received: 12 March 1998/Revised version: 20 April 1998/Accepted: 22 April 1998     

The relative reactivity of 2,3‐dicarbomethoxy‐5‐norbornenes in metathesis polymerization using the original n‐chelating ruthenium carbene complex

¹H NMR spectroscopy is used to study the kinetics of metathesis copolymerization of three isomeric 2,3‐dicarbomethoxy‐5‐norbornenes using the original N‐chelating ruthenium carbene complex. Based on the experimental data the copolymerization constants of isomeric 2,3‐dicarbomethoxy‐5‐norbornenes are calculated. It is shown that the relative reactivity of endic acid dimethyl ester—(1R,2S,3R,4S)‐dimethyl bicyclo[2.2.1]hept‐5‐ene‐2,3‐dicarboxylate is almost two times lower than the corresponding values for (1R,2R,3S,4S)‐dimethyl bicyclo[2.2.1]hept‐5‐ene‐2,3‐dicarboxylate, which confirms earlier findings of steric hindrance in the orientation of the monomer due to the carbene catalyst. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40130.     

Evidence of isomerization of 5-methylenebicyclo[2.2.1] hept-2-ene cation by13C NMR spectroscopy

Summary Cations obtained by reaction of various protonic acids with 5-Methylenebicyclo [2.2.1] hept-2-ene (5-methylene-2-norbornene) have been studied by C NMR spectroscopy. The isomerization of initial carbocation has been pointed out. A correlation of these results with the structure of the corresponding polymers has been establishedThe cationic polymerization of 5-Methylenebicyclo [2.2.1] hept2-ene (5-methylene-2-norbornene) has been investigated several times and KENNEDY (1974) published a review on this topic. A structure of the polymer obtained by classical cationic initiation has been suggested; this results from infrared and X.R. diffraction studies.In a recent work IVIN et al. (1980) reported the¹³C NMR spectrum of a poly[5-methylenebicyclo [2.2.1] hept-2-ene] resulting from a Ziegler-Natta initiation. We obtained the same¹³C NMR spectrum as IVIN et al. when the initiator were TiCl₄, CF₃ COOH, CCl₃COOH and concentrated H₂SO₄ (see fig.1). Chemical shifts and coupling constants fit with the generally accepted structure of the polymers: KENNEDY and MAKOWSKY (1967) suggested an isomerization of the active species:     

‘Tetol’: a stereo-rigid four-strand motif for alkali and alkaline earth metal ion coordination

The tetraalcohol 2,3,5,6-endo,endo,endo,endo-tetrakis(hydroxymethyl)bicyclo[2.2.1]heptane (tetol, 1) has been prepared and crystallises readily as the lithium(I) complex [Li(1)₂]Cl, forming an oligomeric multi-chain structure in which pairs of alcohols from two crystallographically independent tetol molecules bind lithium ions tetrahedrally. However, formation of monomeric structures in solution is inferred from electrospray mass spectroscopy, which has also shown evidence of exchange of lithium ion in the complexed species by added alkaline earth ions.     

Poly(2,5-(3,4-bis(methoxymethyl)furanylene)vinylene)s prepared by aqueous ring opening metathesis polymerisation

Summary Poly(2,5-(3,4-bis(methoxymethyl)furanylene)vinylene)s of various microstructures, prepared by aqueous Ring Opening Metathesis Polymerisation (ROMP) of exo,exo-5,6-bis(methoxymethyl)-7-oxabicylo[2.2.1]hept-2-ene, were characterised by high field NMR.     

二环[2.2.1]庚烷-2,3-二羧酸二钠的合成及表征

以用量为原料质量24.33％的380～830?μm的Raney?Ni为催化剂,在常温常压条件下对二环[2.2.1]庚-5-烯-2,3-二羧酸二钠进行加氢,反应时间90?min,得到聚丙烯成核剂二环[2.2.1]庚烷-2,3-二羧酸二钠,收率达90％以上.在同样条件下,将50％(w)的再生催化剂与50％(w)的新鲜催化剂...     

The synthesis and characterisation of poly( 14-cyclopentenylene-5,6-ethylidene-2,3-disodium dicarboxy1ate)s and Pendant functional group isomerisation

Summary Poly(l,4-cyclopentenylene-5,6-ethylidene-2,3-disodium dicarboxy1ate)s have been synthesised from the exo,exo-, endo,endo- and exo, endo- isomers of dimethyl bicyclo[2.2.l]hept-5-ene-2,3-dicarboxylates in a three step process involving ring opening metathesis polymerisation, hydrogenation and hydrolysis. Exo,exo- and endo,exo- pendant functional group stereochemistries were unchanged throughout these processes, whereas, the Polymers derived from the endo,endo-monomer underwent fragmentation during hydrogenation and isomerisation during hydrolysi s to give to the more stable endo,exo- form of the polymer. Received: 25 July 2002/ Accepted: 7 October 2002 Correspondence to W. J. Feast     

Synthesis and characterization of poly[(2-trimethylsilyl-2-cyclopentene-1,4-diyl)vinylene]

Summary Ring opening metathesis polymerization (ROMP) of 2-trimethylsilylbicyclo [2.2.1]-hept-2,5-diene (I) with a tungsten hexachloride/tetramethyltin co-catalyst system yields poly[(2-trimethylsilyl-2-cyclopentene-1,4-diyl) vinylene] (II). The product polymer (II) has been characterized by¹H,¹³C,²⁹Si, IR and UV-VIS spectroscopy. Its molecular weight distribution has been determined by gel permeation chromatography (GPC), its thermal stability by thermogravimetric analysis (TGA) and its glass transition temperature (Tg) by differential scanning calorimetry (DSC).     

UV‐ and thermally triggered ring‐opening metathesis polymerization for the spatially resolved functionalization of polymeric monolithic devices

Porous polymeric monolithic supports were prepared via electron beam‐triggered free radical polymerization using a mixture of ethyl methacrylate and trimethylolpropane triacrylate in 2‐propanol, 1‐dodecanol and toluene. Bicyclo[2.2.1]hept‐5‐en‐2‐ylmethyl acrylate (1) was grafted onto these monolithic supports in a spatially resolved way with the aid of masks using both electron beam‐ (EB) and UV‐triggered free radical polymerization. The thus immobilized norborn‐2‐ene‐containing graft polymers were further treated with the 2^nd‐generation Grubbs initiator, i.e., RuCl₂(PCy₃)(IMesH₂)(CHPh) (4) (IMesH₂ = 1,3‐dimesitylimidazolin‐2‐ylidene), and then reacted with bicyclo[2.2.1]hept‐5‐en‐2‐ylmethyl pyrene‐1‐carboxylate (2). Alternatively, monoliths completely grafted with poly‐ 1 were surface grafted with 2 in a spatially resolved way in the presence of a latent, UV‐triggerable precatalyst, i.e., [Ru(IMesH₂)(CF₃COO)(t‐BuCN)₄⁺ CF₃COO^?] (5). Finally, to demonstrate the utility of this chemistry, a 2^nd‐generation Grubbs initiator‐based approach was used to prepare a trypsin‐functionalized monolith‐containing chip device that allowed for the online digestion of N‐α‐benzoyl‐L ‐argininethylester hydrochloride. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

rGO/CuO/PEDOT nanocomposite formation,its characterisation and electrochemical performances for supercapacitors

ABSTRACT

Supercapacitor properties of rGO, CuO, PEDOT and rGO/CuO at [rGO]_o/[CuO]_o?=?1:1; 1:1.5; 1:2 and rGO/CuO/PEDOT nanocomposite at [rGO]_o/[CuO]_o/[EDOT]_o?=?1:1:1; 1:1:3; 1:1:5 were investigated using chemical reduction of GO and in-situ polymerisation process. SEM-EDX, HRTEM, BET surface area analysis confirm the nanocomposite formations. Nanocomposite materials are also analysed through FTIR-ATR, Raman, TGA-DTA, GCD, CV and EIS. The highest specific capacitance of C _sp?=?156.7 F/g at 2?mV/s is determined as rGO/CuO/PEDOT at [rGO]_o/[CuO]_o/[EDOT]_o?=?1:1:5. In addition, two-electrode supercapacitor device for rGO/CuO/PEDOT at [rGO]_o/[CuO]_o/[EDOT]_o?=?1:1:5 are found to provide a maximum specific energy (E?=?14.15 Wh/kg at 20?mA) and specific power (P?=?24730 W/kg at 50?mA), electrical serial resistance (ESR?=?13.33 Ω) with good capacity retention after 3000 cycles. An equivalent circuit model of LR1(CR2)(QR3) is proposed to interpret the EIS data. The supercapacitor performance of the rGO/CuO/PEDOT nanocomposite electrode indicates the synergistic effect of hybrid supercapacitors.     

Synthesis and Cytotoxicity of Octahydroepoxyisoindole-7-carboxylic Acids and Norcantharidin–Amide Hybrids as Norcantharidin Analogues

Octahydroepoxyisoindole analogues of norcantharidin were accessed through a Diels–Alder reaction of an amine-substituted furan with maleic anhydride and subsequent reduction of the bicyclo[2.2.1]heptene olefin. Despite retention of the carboxylate and the ether bridgehead known to impart cytotoxic activity to norcantharidin, none of these analogues displayed notable cytotoxicity against the 11 cell lines examined: HT29 (colon), MCF-7 (breast), A2780 (ovarian), H460 (lung), A431 (skin), Du145 (prostate), BE2-C (neuroblastoma), SJ-G2 and U87 (glioblastoma), MIA (pancreatic), and SMA (spontaneous murine astrocytoma). The incorporation of an amino-substituted system post-synthesis of norcantharidin afforded facile access to 14 acid/amide-substituted norcantharidin analogues. Of these, only four displayed sufficient activity at the initial 25 μm compound screening dose to warrant full evaluation of growth inhibition. Common to these analogues was the presence of a 4-biphenyl moiety, and in particular 3-(2-(furan-2-ylmethyl)-3-(4-biphenylamino)-3-oxopropylcarbamoyl)-7-oxabicyclo[2.2.1]heptane-2-carboxylic acid ( 13 c ) and 3-(2-(pyrrole-2-ylmethyl)-3-(4-biphenylamino)-3-oxopropylcarbamoyl)-7-oxabicyclo[2.2.1]heptane-2-carboxylic acid ( 24 ) displayed high levels of cytotoxicity, returning GI₅₀ values of 15 nm (HT29) to 2.9 μm (U87) and 17 nm (SMA) to 2.8 μm (U87), respectively. These are the most cytotoxic norcantharidin analogues reported to date.     

A highly active novel β-nucleating agent for isotactic polypropylene

A highly active novel β-nucleating agent for isotactic polypropylene (iPP), cadmium bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate (BCHE30), was found and its effects on the mechanical properties, the content of β-crystal, and crystallization behavior of iPP were investigated, respectively. The results show that the impact strength and crystallization peak temperature of nucleated iPP are greatly increased, while the spherulite size of nucleated iPP is dramatically decreased than that of pure iPP. The content of β-form of nucleated iPP (k_β value) can reach 87% with 0.1 wt% BCHE30. The Caze method was used to study the non-isothermal crystallization kinetics of nucleated iPP and the crystallization active energy was achieved by Kissinger method.