3,4-Epoxy-1-butene, reaction with

These reactions proceed by initial ozone attack on the C = C bond of the olefin. An intermediate ozonide is formed, which rapidly decomposes to a carbonyl and a biradical. The biradical can be stabilized, or it can decompose. Paulson et al. (1991b) found the products methacrolein, methyl vinyl ketone, and propene, in yields of 68%, 25%, and 7%, respectively. Based on the presence of epoxides in the ozone/isoprene system, Paulson et al. concluded that 0(3P) was being formed. Calculations indicated that 0.45 0(3P) radicals were formed for every ozone/isoprene reaction. However, Atkinson et al. (1993) recently showed that the epoxides were formed directly from the reaction with ozone rather than the reaction with 0(3P). The epoxides formed were l,2-epoxy-2-methy 1-3-butene and l,2-epoxy-3-methyl-3-butene, in yields of 0.028 and 0.011, respectively. There was also definite evidence for the formation of OH radicals in the ozone system, thus causing difficulties in product analyses. Each ozone/isoprene reaction yielded 0.68 OH radicals (Paulson et al., 1991b). 

Cleavage of 3,4-epoxy-3-methyl-1-butene in its reaction with 2,3,5-trimethyl -4-acetoxyphenol at ambient temperature in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium(0) occurred at the more highly-substituted side to give 2,3,6-trimethyl-4-(1-hydroxymethyl-1-methylallyloxy)-phenyl acetate without chroman formation (ref. 179). 

Vinyl-functional alkylene carbonates can also be prepared from the corresponding epoxides in a manner similar to the commercial manufacture of ethylene and PCs via CO2 insertion. The most notable examples of this technology are the syntheses of 4-vinyl-1,3-dioxolan-2-one (vinyl ethylene carbonate, VEC) (5, Scheme 24) from 3,4-epoxy-1-butene or 4-phenyl-5-vinyl-l,3-dioxolan-2-one (6, Scheme 24) from analogous aromatic derivative l-phenyl-2-vinyl oxirane. Although the homopolymerization of both vinyl monomers produced polymers in relatively low yield, copolymerizations effectively provided cyclic carbonate-containing copolymers. It was found that VEC can be copolymerized with readily available vinyl monomers, such as styrene, alkyl acrylates and methacrylates, and vinyl esters.With the exception of styrene, the authors found that VEC will undergo free-radical solution or emulsion copolymerization to produce polymeric species with a pendant five-membered alkylene carbonate functionality that can be further cross-linked by reaction with amines. Polymerizations of 4-phenyl-5-vinyl-l,3-dioxolan-2-one also provided cyclic carbonate-containing copolymers. 

An explanation not easily distinguishable from the one involving resonance with a carbonium ion structure in the transition state is that the reactive species is an ion pair in equilibrium with the covalent molecule. This is quite likely in a solvent insufficiently polar to cause dissociation of the ion pairs. Examples of second order nucleophilic displacements accelerated by the sort of structural change that would stabilize a carbonium ion are of fairly frequent occurrence. Allyl chloride reacts with potassium iodide in acetone at 50° seventy-nine times as fast as does -butyl chloride.209 Another example is the reaction of 3,4-epoxy-1 -butene with methoxide ion.210... 

Citti, L., Gervasi, PG, Turchi, G, Bellucci, G. Bianchini. R. (1984) The reaction of 3,4-epoxy-1-butene with deoxyguanosine and DNA in vitro synthesis and characterization of the main adducts. Carcinogenesis, 5, 47-52... 

Stereospecific Epoxidation of 2-Butene. The hydroperoxide epoxidation reaction is stereospecific. Pure cis- and trans-2-butene were epoxi-dized separately by cumene hydroperoxide. The cis olefin gave exclusively cis epoxide, and the trans olefin gave exclusively trans epoxide. In both cases, the epoxide was the sole product formed from the olefin. They can be distinguished easily by their different retention times on a gas chromatography column of 20% diisodecyl phthalate on Chromosorb W(60-80 mesh). They were also identified by comparing their infrared spectra with authentic samples. 

Evidence for the significant role of the alkoxyaluminohydride ions postulated by Trevoy and Brown11 4 has been secured experimentally by Fuchs and Vender Werf,w who examined the effect on product composition of altering the lithium aluminum hydride-ethylene oxide ratio. In the reaction of 1,2-epoxy-S-butene with approxinuuoU-stoichiometric quantities of reduoing agent, the principal product, l-buten-8-ol, was accompanied by a certain amount of the isomeric substance l-buten-4-ol (Eq, 374). The proportion of the latter mci[Pg.111]

It has boon found by Pudovik and Orlova,ad2a on the other hand, that whereas 1,2-epoxy-2-methyI-3-butene yields on treatment with alkyl mercaptans in base a mixture in which the produot formed by terminal attack is preponderant, the use of boron trifluoride to catalyze the reaction reverses the trend (Eq, 65 a). 

We have also determined that the reaction of (Z)-2-butene-l, 4-diol with DTPP in refluxing dichloromethane (CH2CI2) affords 2,5-dihydrofuran (85-87% GLC and 60% isolated yield). On the other hand, treatment of (E)-2-butene-l,4-diol with DTPP in chloroform (61°, 18 h) gave a distilled material (42%) whose 1H NMR spectrum was completely superimposable on an authentic sample of 3,4-epoxy-l-butene (13). This result is in agreement with the ring closure predictions of Baldwin where the "3-exo-trig" cy-clization is predicted to be favored (2). 

When an unsymmetrical secondary alcohol is formed, depending on which carbon-oxygen bond is cleaved. With propylene oxide, for example, a base-catalyzed reaction favors the formation of the secondary alcohol almost exclusively, whereas, a non-catalytic or acid-catalyzed alcoholysis yields a mixture of the isomeric ethers. However, the reactions of other a-epoxides, such as 3,4-epoxy-l-butene, 3,4-epoxy-l-chloropropane (epichlorohydrin), 3,4-epoxy-l-propanol (glycidol), and styrene oxide, are more complicated with respect to which isomer is favored. ... 

A highly effective catalytic method for alkynylation of epoxides has recently been reported this involves the chelation-controlled alkylation of hetero-substituted epoxides with Mc3A1 and alkynyllithiums via pentacoordinate organoaluminum complexes [82]. For instance, reaction of epoxy ether, (l-benzyloxy)-3-butene oxide (75) in toluene with PhC = CLi under the influence of catalytic MesAl (10 mol%) proceeded smoothly at 0 °C for 5 h to furnish the alkynylation product l-(benzyloxy)-6-phenylhex-5-yn-3-ol (76) in 76 % yield. The yield of the product was very low (3 %) without MeaAl as catalyst under similar conditions. This is the first catalytic procedure for amphiphilic alkylation of epoxides. The participation of pentacoordinate MesAl complexes of epoxy ethers of type 75 is emphasized by comparing the reactivity with the corresponding simple epoxide, 5-phenyl-l-pentene oxide (77), which was not susceptible to nucleophilic attack of PhC s CLi with catalytic Me3Al under similar conditions (Sch. 50). 

The reaction could not be carried out with the usual sulfonic acid ion-exchange resin, because its maximum use temperature was 120°C. The product cannot be made directly from acetone and aniline owing to the formation of a dihydroquinoline by-product (from two molecules of acetone and one of aniline). A shape-selective zeolite might allow the reaction to take place without formation of this byproduct. An inexpensive way of making this diamine from acetone and aniline, similar to the preparation of bisphenol A from acetone and phenol, could lead to new families of polyamides, polyimides, polyureas, polyurethanes, and epoxy resins. A palladium catalyst supported on Nafion dimerized ethylene much faster in water than in organic solvents. The butene was easy to separate.18... 

Rate coefficients for the reactions of OH and O3 with 2- and 3-methyl-3-butene-1,2-diol and l,2-epoxy-3-methyl-3-butene, the latter having been reported very recently as product from isoprene + O3 [11], were determined by use of a relative rate technique. In the O3 experiments sufficient CO was added to scavenge > 90 % of OH radicals eventually being formed. For the O3 reaction of the diols absolute measurements were carried out in addition by monitoring the decay of O3 under pseudo-first order conditions. Absolute and relative rate data were in good agreement. The average values at 295 2 K are ... 

The functionalization of polymeric organolithium compounds with 3,4-epoxy-1-butene (EPB) provides the potential to prepare a polymer molecule with dual functionality as well as a potential precursor to a diene-functionalized macromonomer. It has been shown that the reaction of EPB with methyllithium results in three modes of addition to the... 

The Pd(PhCN)2Cl2-catalyzed cross-coupling reaction of 1-alkenylboronic reagents with 3,4-epoxy- 1-butene afforded a mix-toe of 2-(l-vinyl)-3-alkenols and alka-2,5-dienols (eq 21). ... 

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