With dicyclopentadiene

The highly aromatic resins are often used as coumarone/indene resin substitutes. A range of soft aromatic resins is available, produced from the alkylation of xylene and other aromatic hydrocarbons with dicyclopentadiene. These are excellent softeners for a wide range of rubbers. In common with other aromatic materials derived from petroleum sources, some of the resins used within the rubber industry are deemed to be carcinogenic. 

Codimerization of butadiene with dicyclopentadiene (example 8, Table II) was shown to proceed via a crotyl-nickel complex (62). Ring contraction of cyclooctadiene (example 10, Table II) appears to be a hydride promoted reaction. The hydride-promoted dimerization of norbomadiene to -toly 1 norbornene (example 9, Table II) appears to be quite different from dimerization via a metallacycle (see Table I, example 16). 

Norbornene can be prepared by the Diels-Alder reaction of ethylene with dicyclopentadiene.4 It can be purchased from Matheson Coleman and Bell or the Aldrich Chemical Company, Inc. 

Beginning with dicyclopentadiene, it has also proven possible to prepare 442 which could serve in its own ri t as a tetraquinane precursor... 

The diacetate of 711 has also been produced in stereoselective fashion via a route beginning with dicyclopentadiene (Scheme LXXVI) Ketone 712 was transformed into dimethylated alcohol 713 whose ozonolysis provided 714. Following Jones oxidation, decarboxylation with concomitant introduction of a double bond was realized by application of Kochi s prowdure. A lengthy quence of steps to adjust functionality led up to annulation by a modified Wichterle sequence. The conversion of 715 to 716 was accomplish by standard reactions. 

A 1-liter autoclave was charged with dicyclopentadiene (1.75 mol), allyl acetate (4.2 mol), and hydroquinone (1 g) and then stirred at 180°C for 9 hours in a closed system at 300 rpm. It was then filtered and volatile components evaporated. The residue was distilled twice at 86°C 10 mmHg and 358 g of product isolated. 

Figure 2. Change in stress-strain behavior with time, with dicyclopentadiene polymerized sulfur...

Figure 6.7 Simplified scheme of the peroxide curing of EPDM with dicyclopentadiene...

Bis (cyclopentadienyliron dicarbonyl) is available commercially from several sources, for example, Strem Chemicals, Inc., 150 Anders St., Danvers, Mass. 01923. If the commercial source is not used, (C HjFe(CO) J can be prepared by treatment of Fe(CO) with cyclopentadiene in an autoclave or, better, with dicyclopentadiene in an open flask. See Inorganic Syntheses, 7, 110 (1963). - > ... 

Figure 15.9 shows the esterification of different saturated carboxylic acids with dicyclopentadiene. In all depicted experiments the carboxylic acid/dicyclo— pentadiene molar ratio is about 4 and the amount of catalyst is 10% by weight of dicyclopentadiene at a reaction temperature of 80°C. In this reaction the Nafion/silica composite catalyst is more active compared to the Amberlyst resin, in particular with respect to the amount of the acid groups on the resin. 

Sulfur Modified with Dicyclopentadiene. The beneficial use of dicyclopentadiene to modify sulfur has been reported by a number of workers including Currell et al. (3), Sullivan et al. (4), and also Diehl (5). Currell et al. showed that the interaction of dicyclopentadiene and elemental sulfur at 140 °C gives a mixture of polysulfides and free elemental sulfur which, even after standing for 18 mo, is held as a mixture of presumably monoclinic and noncrystalline sulfur. Sullivan et al. reported that the minimum concentration of dicyclopentadiene required to stop permanently the embrittlement of elemental sulfur is 13% if the reaction temperature is less than 140°C and only 6% if the reaction temperature is greater than 140 °C. Presumably the polysulfide reaction products form a solid solution with the unreacted sulfur from which orthorhombic sulfur cannot crystallize. 

Increases in the UTS of the polypropylene fabric by impregnation with sulfur materials ranged from 24 to 87% the highest increases were obtained with dicyclopentadiene-modified sulfur materials. Merely heat-... 

Plastic Sulfur Stabilization by Copolymerization of Sulfur with Dicyclopentadiene... 

Sulfur Concrete Modified with Dicyclopentadiene (DCP). DCP was a better plasticizer for improving the strength of the binder. When DCP is used to modify sulfur, one can state the following quantitative viscosity changes depending on the reaction temperature, the reaction time, and the concentration of DCP (Figures 10a and b). Optimal... 

Hofmann and von Narbutt (5J) in 1908 described some compounds formed by the reaction of aqueous potassium chloroplatinate(II) in aqueous alcohols (ROH) with dicyclopentadiene. They formulated them as (XI) in which ROPtCl had added across one of the double bonds of the diene. This formulation could not be correct because it... 

The reaction is akin to the Ritter reaction, with activation achieved by nitration, rather than proton-ation, and the products accordingly retain the nitro group. Additions to 1-phenylcyclohexene (59%) and to franr-stilbene (72%) are stereospecific (trans) cfr-stilbene gives the expected tfireo product (39%) plus some erythro (6%). Reactions of nitrogen dioxide with alkenes are very complex and rarely use-ful. A recent mechanistic paper gives many key references. " Addition of NjOs is occasionally usefiil, as with dicyclopentadiene (Scheme 49). ... 

With dicyclopentadiene, both cuprous chloride and cuprous bromide form a 1 1 complex which decomposes above about 110°C (523). The infrared spectra indicate complexing of only one double bond of the olefin and Schrauzer and Eichler (523) have suggested the structure (220) in which complexing takes place at the cyclopentene side of the molecule. 

Booth et al. (M3) carried out the reaction of [Mn(CH3)(CO)j] with cyclo-pentadiene and found the reaction to be so slow that dimerization of cyclopentadiene occurred before reaction with [Mn(CH3)(CO)5] [Eq. (40)]. The reaction of [Mn(R)(CO)j] (R = CH3, Ph) with dicyclopentadiene directly, however, also gave a 1 2 adduct [Eq. (41)]. The reaction of [Mn(CH3)(CO)5] with norbomadiene, which gave a mixture of the 1 1 and 1 2 adducts, was also reported in this study. Other studies with different alkenes and alkynes gave the same type of products (M4,M5). 

Instead of sulfuric acid, phosphoric acid can also be used as the acid. Under special circumstances the olefin for the further catalysis may serve as a solvent itself. This concept was successfully realized with dicyclopentadiene (DCP). 

Cyclopentadienyl complexes are often prepared as dimeric species, but less frequently as higher clusters. Several techniques are used to prepare cyclopentadienyl dimers. A generally useful reaction is of a mononuclear carbonyl with dicyclopentadiene. The proper conditions for preparation of Cp2Fe2(CO)4 have been studied . ... 

Co-polymerization of ethylene with cyclic dienes such as 1,3-cyclopentadiene, dicyclopentadiene, and 4-vinyl-l-cyclohexene using rac-C2H4(Ind)2ZrCl2 showed that dicyclopentadiene was the most reactive co-monomer. 1,3-Cyclopentadiene rapidly dimerizes to dicyclopentadiene, and thus ethylene/l,3-cyclopentadiene co-polymerization actually resulted in ethylene/l,3-cyclopentadiene terpolymers with dicyclopentadiene. Co-polymers with more than 9mol% of the co-monomer did not show a melt transition.1058... 

With this background of information, Alder and Stein were surprised to find that phenyl azide reacts exothermally at room temperature with dicyclopentadiene to form a monoadduct, m.p. 130-131°, in quantitative yield. Two formulas had been advanced for dicyclopentadiene. Kramer and Spilker, discoverers of cyclopen-tadiene, assigned to the dimer the symmetrical cyclobutane structure (1), resulting from dimerization analogous to the formation of the truxillic acids from cinnamic acid. Wieland suggested the unsyrametrical formula (2), resulting from 1,4-addition of one molecule to the double bond of another. Two lines of evidence favored the... 

Higher molecular weight products can be formed by extended reaction of 4-methylphenol with dicyclopentadiene which in turn can then be reacted with isobutene (ref.99) to furnish complex mixtures which serve as excellent antioxidants for use in rubber. 

EPDM (EPR- with -dicyclopentadiene, alloys could be shaped into articles with Fischer, 1972... 

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