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5- vinyl-2-norbornene

Benzophenone-sensitized photoreaction of cyclopentadiene/1,3-butadiene mixtures gave three cross products (Sch. 11). Two [4+2] adducts 52 and 53 were formed, with the vinyl norbornene 52 as the dominant [4+2] isomer. Cyclobutane 54, a mixture of two isomers, was the major product. One isomer of 54 rearranges to the norbornene 52 while the other isomer rearranges to the [4+4] adduct 55 [48]. [Pg.245]

Another novel addition is that of Pd-Cl to vinyl norbornene (292), which occurs in the trans-exo mode found for noncarbanoid nucleophiles. [Pg.427]

TYPICAL COMONOMERS Ethene, propene, ethylidene norbornene (ENB) or dicyclopentadiene or (DCPD), 1,4 hexadiene (4,4 HD), or vinyl norbornene (VNB) or norbornadiene (NBD). - ... [Pg.103]

EPDM formulations are increasingly popular for medium-voltage, up to 105°C continuous-use temperature, wire and cable covering. EPDMs are good vulcan-izates, providing improved wet electrical properties. When diene vinyl norbornene is incorporated on the EPDM backbone by a gel-free process, a significantly improved EPDM terpolymer is obtained for wire and cable applications. [Pg.170]

Where the diene provides terminal unsaturation, radical addition at the double bond may occur successively in a chain reaction akin to polymerization so that one peroxide radical could produce many cross-links, i.e. to give a cross-linking efficiency greater than 1. Such results have been observed with EPDM rubbers based on methylene norbornene and on vinyl norbornene. [Pg.339]

The cyclohexadiene derivative 130 was obtained by the co-cyclization of DMAD with strained alkenes such as norbornene catalyzed by 75[63], However, the linear 2 1 adduct 131 of an alkene and DMAD was obtained selectively using bis(maleic anhydride)(norbornene)palladium (124)[64] as a cat-alyst[65], A similar reaction of allyl alcohol with DMAD is catalyzed by the catalyst 123 to give the linear adducts 132 and 133[66], Reaction of a vinyl ether with DMAD gives the cyclopentene derivatives 134 and 135 as 2 I adducts, and a cyclooctadiene derivative, although the selectivity is not high[67]. [Pg.487]

In a 200-ml three-necked flask fitted with a dropping funnel (drying tube) is placed a solution of 13.4 g (0.12 mole) of 1-octene in 35 ml of THF. The flask is flushed with nitrogen and 3.7 ml of a 0.5 M solution of diborane (0.012 mole of hydride) in THF is added to carry out the hydroboration. (See Chapter 4, Section I regarding preparation of diborane in THF.) After 1 hour, 1.8 ml (0.1 mole) of water is added, followed by 4.4 g (0.06 mole) of methyl vinyl ketone, and the mixture is stirred for 1 hour at room temperature. The solvent is removed, and the residue is dissolved in ether, dried, and distilled. 2-Dodecanone has bp 119710 mm, 24571 atm. (The product contains 15 % of 5-methyl-2-undecane.) The reaction sequence can be applied successfully to a variety of olefins including cyclopentene, cyclohexene, and norbornene. [Pg.114]

The formation of cyclic sulfinic esters (sultines) from vinyl sulfenes is known , and the trapping of the expected intermediate vinyl sulfene in the thermolysis of thiete dioxide (6fc and 194) has been convincingly achieved . Specifically, thermolysis of thiete dioxide 6b in the presence of norbornenes gave cycloadducts of the Diels-Alder type (i.e. 252b), resulting from the trapping of the vinyl sulfene formed. The accumulated evidence thus supports the proposed mechanism for these thermolytic reactions. [Pg.452]

The 0/7/fo-alkylation of aromatic ketones with olefins can also be achieved by using the rhodium bis-olefin complex [C5Me5Rh(C2H3SiMe3)2] 2, as shown in Equation (9).7 This reaction is applied to a series of olefins (allyltrimethyl-silane, 1-pentene, norbornene, 2,2 -dimethyl-3-butene, cyclopentene, and vinyl ethyl ether) and aromatic ketones (benzophenone, 4,4 -dimethoxybenzophenone, 3,3 -bis(trifluoromethyl)benzophenone, dibenzosuberone, acetophenone, />-chloroacetophenone, and />-(trifluoromethyl)acetophenone). [Pg.215]

Ballantyne B, Myers RC, Klonne DR Comparative acute toxicity and primary irritancy of the ethylidene and vinyl isomers of norbornene.y Appl Toxicol 17(4) 211-221, 1997... [Pg.336]

Silca, crystalline-quartz, 628 Chromyl chloride, 175 Fthylidene norbornene, 335 Methomyl, 443 Cobalt hydrocarbonyl, 182 Decaborane, 203 Benomyl, 67 Diborane, 211 Pentaborane, 555 Osmium tetroxide, 546 Cesium hydroxide, 131 Alumina trihydroxide, 38 Aluminum oxyhydroxide, 38 Vinyl toluene, 738 Nonylphenol, 541 2,4-Dinitrotoluene, 279 Trimethyl benzene, 712 Methylcyclohexanol, 465 Terphenyls, 656 Isooctyl alcohol, 409 Anisidine, 52... [Pg.760]

Irradiation of the epoxy dinitrile 90 in a solution of acetonitrile formed the stabilized ylide 91 that was trapped with ethyl vinyl ether, producing both exo and endo adducts 92 and 93 in 25 and 8% yields. Studies with other dipolarophiles (27) such as norbornene and methyloxazoline generated cycloadducts 94 and 95, respectively, in low overall yield. [Pg.268]

The Heck reaction yields the final product through a p-hydride elimination whereas hydroarylation or hydrovinylation generates the final product via a reductive elimination. Nonetheless, both reactions share a common first step, that is, addition of an aryl or a vinyl palladium species to an alkene, and thus are briefly discussed here. Norbornene 595 is the most studied alkene to evaluate an the... [Pg.494]

Olefinic dipolarophiles, such as dimethyl fumarate, fumaronitrile, ethyl vinyl ether, A-phenylmaleimide, norbornene, and norbornadiene, react with... [Pg.15]

Copolymers of ethylene (E) or propylene (P) with acrylic acid (AA) or methacrylic acid (MA) were obtained from SP2 (USA) and used as received (EAA, PAA, PEAA, PMA). Copolymers of ethylene and vinyl alcohol (EVOH) were prepared by hydrolysis (NaOH 0,5M in methanol, reflux, 48 h), of commercial ethylene-vinyl acetate copolymers (EVA, Elf-Atochem) containing 5, 9, 14, and 18 w% of acetate. Hydroperoxides of EPDM based on 5-ethylidene-2-norbornene (0.7 mol Kg 1, Exxon) and polyoctenamer (Vestenamer, VEST, Hiils) resulted from a reaction of polymer films with singlet oxygen. [Pg.21]

Chloromethyl polystyrene can be converted to a free-radical initiator by reaction with 2,2,6,6-tetramethylpipcridinc-/V-oxyl (TEMPO). Radical polymerization of various substituted alkenes on this resin has been used to prepare new types of polystyrene-based supports [123]. Alternatively, cross-linked vinyl polystyrene can be copolymerized with functionalized norbornene derivatives by ruthenium-mediated ringopening metathesis polymerization [124],... [Pg.25]

Epoxidation of cycloaikenes Cycloalkenes, particularly strained bicyclic alkenes, can be epoxidized by treatment with l equiv. of 1 under N,. In the case of norbornene (2) the reaction involves formation of the metallacycle 3, which decomposes slowly to exo-epoxynorbomene (4). In fact, epoxidation is favoured over ox idation of a vinyl system in the air oxidation of 5 catalyzed with l. 3... [Pg.365]

Aryl cyanides add to norbornene and norbornadiene under nickel catalysis to give (2/U,35 )-3-aryl-2-cyanobicyclo[2.2.11heptanes and (2/U,3.S )-3-aryl-2-cyanobicy-clo[2.2.1]hept-5-enes in good yields with a broad substrate scope. On the other hand, the reaction of an aryl cyanide with triethoxy(vinyl)silane gives a Heck-type arylation product, suggesting the arylnickelation pathway in the catalytic cycle.68... [Pg.329]

An unusual rhodium-catalysed addition of a dienylboronate ester to highly strained alkenes, such as norbornene, has been reported, resulting in the formation of vinyl-cyclopropane-fused tricyclic products (Scheme 7). Preliminary mechanistic studies have been presented.246... [Pg.367]

The isomerization of 5-vinyl-2-norbornene to 5-ethylidene-2-norbornene has been performed using a catalytic system consisting of an alkali metal hydride and an amine. The activity of the alkali metal hydride increased with increasing size of the alkali metal KH > NaH > LiH. Among the various amines tested, only aliphatic 1,2-diamines exhibited the activity for the isomerization. Electron paramagnetic resonance (EPR) and UV-visible spectroscopic experiments on the active species suggest that the isomerization of 5-vinyl-2-norbornene proceeds through a radical mechanism.167... [Pg.503]


See other pages where 5- vinyl-2-norbornene is mentioned: [Pg.40]    [Pg.27]    [Pg.414]    [Pg.408]    [Pg.302]    [Pg.2965]    [Pg.40]    [Pg.27]    [Pg.414]    [Pg.408]    [Pg.302]    [Pg.2965]    [Pg.1055]    [Pg.452]    [Pg.333]    [Pg.63]    [Pg.280]    [Pg.413]    [Pg.214]    [Pg.220]    [Pg.337]    [Pg.311]    [Pg.315]    [Pg.23]    [Pg.16]    [Pg.440]    [Pg.447]    [Pg.716]    [Pg.20]    [Pg.300]    [Pg.2226]    [Pg.392]   
See also in sourсe #XX -- [ Pg.267 ]

See also in sourсe #XX -- [ Pg.267 ]




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5-Vinyl-2-norbornene isomerization

Norbornen

Norbornene

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