Vmyl ethers

Asymmetnc tandem cycloaddicion of a chiral carbohydrate tutroalkene with ethyl vmyl ether in the ptesence of electron-withdrawmgalkenes produces a facile assembly of bicychc systems, which can further be seletnvely cleaved to give homologated carbohydrates fEq 8 110 ... 

The syntheac potenQ of the tandem [4+2 /[3+2 cycloadchtion process is greatly enhanced by the employment of vmyl ether dienophiles For example, the nse of vmyl bntyl ether as a chenophile leads to a tnoyclic nirroso acetal, which gives a tncyclic lactam, as shown m Eq 8113... 

Vmyl ethers can also be formulated with acrylic and unsatiiraterl polyesters containing maleate or fumarate functionality. Because of their ability to form alternating copolymers by a free-radical polymerization mechanism, such formulations can be cured using free-radical photoinitiators With acrylic monomers and oligomers, a hybrid approach has been taken using both simultaneous cationic and free-radical initiation. 

Takakura, T. CTFE-Vmyl Ethers Copolymers in Modem Fluoropolymers, Scheirs, J., Ed. John Wiley Sons, Inc. New York, 1997 Chapter 29, p 557. 

Rezanova, E. N. Lichtenthaler, R. N. Excess properties of binary mixtures of an alkanol or an alkane with butyl-vmyl ether or... 

An unlimited number of organic esters can be prepared by reactions of poly(vmyl alcohol) employing standard synthesis. Ethers of poly(vinyl alcohol) are easily formed. Insoluble internal ethers are formed by the elimination of water, a reaction catalyzed by mineral acids and alkali. 

A diastereoselective formal addition of a 7ra i-2-(phenylthio)vmyl moiety to a-hydroxyhydrazones through a radical pathway is shown in Scheme 2.29. To overcome the lack of a viable intermolecular vinyl radical addition to C=N double bonds, not to mention a reaction proceeding with stereocontrol, this procedure employs a temporary silicon tether, which is used to hold the alkyne unit in place so that the vinyl radical addition could proceed intramolecularly. Thus, intermolecular addition of PhS" to the alkyne moiety in the chiral alkyne 161 leads to vinyl radical 163, which cyclizes in a 5-exo fashion, according to the Beckwith-Houk predictions, to give aminyl radical 164 with an a 7z-arrangement between the ether and the amino group. Radical reduction and removal of the silicon tether without prior isolation of the end product of the radical cyclization cascade, 165, yields the a-amino alcohol 162. This strategy, which could also be applied to the diastereoselective synthesis of polyhydroxylated amines (not shown), can be considered as synthetic equivalent of an acetaldehyde Mannich reaction with acyclic stereocontrol. 

Banerjee, P., Bhattacharyya, S.N., and Mandal, B.M. (1996) Poly(vmyl methyl ether) stabilized colloidal polyaniline dispersions. Langmuir, 12, 1406—... 

CavaiDe, J.Y., Perez, J., Jourdan, C., and Johari, G.P. (1987) Dynamic mechanical behavior of poly(vmyl-methyl ether)-poly (styrene) blends. J. Pdym. Sci. B Polym. Phys., 25 (9), 1847-1858. 

Stadler, R., de Lucca Freitas, L.L., Krieger, V, and Klotz, S. (1988) Influence of the phase separation on the linear viscoelastic properties of a polystyrene-poly(vmyl methyl ether) blend. Polymer, 29 (9), 1643-1647. 

Figure 9.4. Master curves for a poly(vmyl methyl ether) with a molecular weight of 138,000. Data of Diana Hess.

Partial specific volume of poly(vmyl methyl ether)... 

PVMMA Poly(vmyl methyl ether-co-malic anhydride)... 

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