Norbomene anhydride

Diels-Alder Reactions. The important dimerization between 1,3-dienes and a wide variety of dienoplules to produce cyclohexene derivatives was discovered in 1928 by Otto Diels and Kurt Alder. In 1950 they won the Nobel prize for their pioneering work. Butadiene has to be in the j -cis form in order to participate in these concerted reactions. Typical examples of reaction products from the reaction between butadiene and maleic anhydride (1), or cyclopentadiene (2), or itself (3), are <7 -1,2,3,6-tetrahydrophthaHc anhydride [27813-21 -4] 5-vinyl-2-norbomene [3048-64-4], and 4-vinyl-1-cyclohexene [100-40-3], respectively. 

Lipase-catalyzed enantioselective transesterification of 0-substituted-l,2-diols is another practical route for the synthesis of P-blockers. Lipase PS suspended in toluene catalyzes the transesterification of (63) with vinyl acetate to give the (5)-ester in 43% yield and >98% ee (78). The desired product, optically pure (R)-ttitylglycidol, is then easily obtained by treating the ester with alcohoHc alkaU. Moreover, Pseudomonas Hpase catalyzes the acylation of oxazohdinone (64) with acetic anhydride in very good yield and selectivity (74). PPL-catalyzed transesterification of a number of /n j -norbomene derivatives proceeds in about 30% yield and 92% ee (79,80). 

Cycloaddition of bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic anhydride 81 with cyclopentadiene was also studied by Bartlett et al., who found exclusive top addition, the top-endo/top-exo ratio being 3 2 [147]. The endolexo ratio is significantly different from that of 80 (60-70 1). The observed top selectivity in norbornadiene (80) and norbomene (81) derivatives is consistent with the inherent top reactivity of norbomanone 25 and norbomene 57. Orbital unsymmetrization of the dienophile... 

The photocycloaddition of dimethyl maleate to norbomene yields cyclobutanes (91) and (92), while the photocycloaddition of maleic anhydride to this olefin yields (92) and (93) (after hydrolysis)<100> ... 

As in the photoaddition of maleic anhydride to norbomene, the endo product (93) may arise from a charge-transfer complex. 

Norbomene end-capped polyimide oligomers (trade name LARC) are obtained by including 5-norbomene-2,3-dicarboxylic anhydride (nadic anhydride) (XLVII) in the polymerization reaction between a dianhydride and diamine [de Abajo, 1988 Hergenrother, 1987]. Heating the oligomer at 270-320°C results in a thermoset product. The main reaction... 

Another important use of BC13 is as a Friedel-Crafts catalyst in various polymerization, alkylation, and acylation reactions, and in other organic syntheses (see Friedel-Crafts reaction). Examples include conversion of cydophosphazenes to polymers (81,82) polymerization of olefins such as ethylene (75,83—88) graft polymerization of vinyl chloride and isobutylene (89) stereospecific polymerization of propylene (90) copolymerization of isobutylene and styrene (91,92), and other unsaturated aromatics with maleic anhydride (93) polymerization of norbomene (94), butadiene (95) preparation of electrically conducting epoxy resins (96), and polymers containing B and N (97) and selective demethylation of methoxy groups ortho to OH groups (98). 

Poly(ethylene-co-norbomene-2,3-dicarboxylic acid anhydride) was prepared by co-polymerizing the respective monomers with the transition metal catalyst, di(3-t-butyl-2-hydroxy-l-(A-phenyhmino)benzene) titanium(IV). The polymerization was conducted at ambient temperature using methylaluminoxane as co-catalyst. After a 10 minute polymerization reaction scoping period 0.02 mol% of norbornene-2,3-dicarboxylic acid anhydride was incorporated into the co-polymer. 

In a subsequent investigation by the author poly(ethylene-co-norbornene dicar-boxylic acid anhydride) containing 0.03 mol% norbomene-2,3-dicarboxylic acid anhydride was prepared using the Step 2 vanadium analogue, (I). 

Some thermosets are made with maleic anhydride only, or with other unsaturated 1,2-dicarboxylic acids or anhydrides such as itaconic acid or methylenesuccinic acid [7], chlorendic acid or 1,4.5,6,7,7-hexachloro-5-norbornene-2,3-dicarboxylic acid (or anhydride), 1,4.5,6,7-pentachloro-5-norbornene-2,3-dicarboxylic acid anhydride or 1,4.5,6-tetrachloro-5-norbornene-2,3-dicarboxylic acid anhydride. These norbomene derivatives can be obtained from the Diels-Alder condensation of the chlorinated cyclopenta-1,3-dienes and maleic anhydride, as shown in the following reaction ... 

S.F. Parker, K.P.J. Williams, D. Steele H. Herman (2003). Phys. Chem. Chem. Phys., 5, 1508-1514. The vibrational spectra of norbomene and nadic anhydride. 

Fig. 10.23 The chemistry of PMR-15. The first stage is imidisation of the reactants, nadic anhydride monomethyl ester (NE), methylene dianiline (MDA) and 3,3 ,4,4 -benzophenonetetracarboxylic acid dimethyl ester (BTDE). The second stage is cross-linking of the norbomene end-caps.

Keywords large scale, gas-solid reaction, catalytic hydrogenation, norbomene dicarboxylic anhydride, stereospecific... 

Sulfonation was carried out by heating the asphalt with sulfur trioxide-trimethyl amine complex or sulfur trioxide-pyridine complex at temperatures near 135°C. Sulfamic acid treatment was also included in this series. Many other reagents were evaluated such as methyl methacrylate, 2-acrylamido-2-methylpropanesulfonic acid, 2-dimethyl-aminoethyl methacrylate, 2-vinylpyridine, 4-vinylpyridine, tetrahydro-phthalic anhydride, norbomene dicarboxylic anhydride, and phthalic anhydride. 

Figure 2 shows the dramatic increase in viscosity that results when maleic anhydride is added to asphalt. This increase occurs even in the absence of any added catalyst or peroxide initiator. Other anhydrides such as phthalic anhydride and 5-norbomene-2,3-dicarboxylic anhydride were not as effective. Note that there is no noticeable change in the viscosity of the unmodified asphalt. 

This reagent is prepared by the reaction of 5-norbomene-e do-2,3-dicar-boxy lie anhydride with hydroxylamine (91% yield). ... 

Elastomeric ionomers have also been developed from ethylene-propylene-diene ternary copolymers known as EPDM rubbers. The diene is commonly ethylidene norbomene. Du Pont made carboxylated ionomers by free-radical grafting of maleic anhydride (0.5—5%) onto the diene moiety of the polymer and neutralized the product with rosin salt. The ethylidene norbomene can also be sulfonated, thus ... 

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