Isopropyl Vinyl Ether Research Articles

13C nuclear magnetic resonance studies on the stereochemical configurations of 2,4‐dimethoxypentane and poly(alkyl vinyl ethers)

Abstract13C nuclear magnetic resonance (CMR) spectra were obtained for 2,4‐dimethoxypentane, which is a model compound of poly(methyl vinyl ether), and the effects of the solvent and temperature on the chemical shifts were investigated. CMR spectra of poly‐(alkyl vinyl ethers) were also determined and analyzed. The diad tacticities were obtained from β‐methylene carbon resonances of poly(methyl vinyl ether), poly(ethyl vinyl ether), and poly(isobutyl vinyl ether), but not from those of poly(isopropyl vinyl ether) and poly(tert‐butyl vinyl ether). The methoxyl carbon resonance of poly(methyl vinyl ether) and the ethoxyl methylene carbon resonance of poly(ethyl vinyl ether) showed splittings corresponding to pentad and triad sequences, respectively. The α‐methine and quaternary carbon resonances of poly(tert‐butyl vinyl ether) showed splittings corresponding to pentad and triad sequences, respectively.

Reaction of alkyl vinyl ethers with d-galactose diethyl dithioacetal

d-Galactose diethyl dithioacetal was brought into reaction, under acid catalysis, with each of several alkyl vinyl ethers in equimolar quantities. The major reaction product, 5,6- O-ethylidene- d-galactose diethyl dithioacetal, was isolated and its structure was proved by reductive desulfurization with subsequent periodate oxidation. This structure was confirmed by mass spectral data. When ethyl vinyl ether was used, the minor reaction-product was 6- O-(1-ethoxyethyl)- d-galactose diethyl dithioacetal. A pathway is proposed for this reaction. 5,6- O-Ethylidene- d-galactose diethyl acetal was partially demercaptalated to ethyl 5,6- O-ethylidene-1-thio-α- d-galactofuranoside, whose structure was confirmed through its synthesis by the reaction of isopropyl vinyl ether with ethyl 1-thio-α- d-galatofuranoside under acid catalysis.

Long range coupling involving alkoxy protons in vinyl ethers

The nuclear magnetic resonance spectra of methyl vinyl ether and isopropyl vinyl ether are reported and the long range HH coupling constants are discussed.

The thermal decomposition of alkyl vinyl ethers. Part II. The inhibited decompositions of t-butyl, isopropyl, and 2-chloroethyl vinyl ethers

The kinetics of the thermal decompositions of t-butyl, isopropyl and 2-chloroethyl vinyl ethers into predominantly olefins and acetaldehyde in a seasoned vessel have been studied in a static system. These reactions are homogeneous and essentially unimolecular; they obey first-order kinetics in their early stages. The rate constants are: t-butyl vinyl ether (215–324°), k= 1010·86 exp(–36,184/RT); isopropyl vinyl ether (311·0–375·0°), k= 1012·12 exp(–42,557/RT); 2-chloroethyl vinyl ether (353·0–424·0°), k= 1011·49 exp(–44,752/RT) sec.–1.

Polymerization of alkyl vinyl ethers in presence of the sulfuric acid ? aluminum sulfate complex

In presence of the sulfuric acid — aluminum sulfate complex at 20° stereoregular polymers were prepared from ethyl vinyl, propyl vinyl, isopropyl vinyl, and isobutyl vinyl ethers in yields of 80–90%.

Addition of aliphatic ?-nitro alcohols to vinyl ethers

1. The addition of various aliphaticβ-nitro alcohols to ethyl, isopropyl, and butyl vinyl ethers has been carried out for the first time, and the resulting acetals have been characterized. 2. Some of the acetals synthesized were hydrolyzed with regeneration of the original nitro alcohol.

Stepwise synthesis of poly (isopropyl vinyl ether)

1. 1,1,3-Triisopropoxybutane, 1,1,3,5-tetraisopropoxyhexane, and 1,1,3,5,7-pentaisopropoxyoctane were synthesized and characterized. 2. The hydrolysis of the isopropoxy compounds was carried out.

Viscosity constant for polymers of vinyl ethers

1. On the basis of a study of the molecular weights and viscosities of solutions of alkoxy compounds and separate fractions of poly(alkyl vinyl ethers) the constant of Staudinger's formula was determined for the polymers of ethyl vinyl, isopropyl vinyl, and butyl vinyl ethers. 2. The effect of the chemical structure of the alkoxy group in polymers of vinyl ethers on the constant Km in Staudinger's formula was shown.

Reactions of unsaturated and macromolecular compounds Communication 9. Copolymerization of isopropyl vinyl ether with methyl acrylate

1. Reaction proceeds between methyl acrylate and isopropyl vinyl ether in presence of the initiators benzoyl peroxide and 2,2′-azobis[2-methylpropionitrile] with formation of copolymers. 2. As the concentration of isopropyl vinyl ether in the reaction medium increases, the yield of copolymer falls, but the proportion of isopropyl vinyl ether units in the copolymer increases. 3. Copolymers prepared in presence of 2,2′-azobis[2-methylpropionitrile] contain a somewhat higher proportion of isopropyl vinyl ether units than copolymers prepared in presence of benzoyl peroxide. 4. In spite of the use of a very great excess of isopropyl vinyl ether in the reaction mixture, it was not found possible to raise the content of vinyl ether units in the copolymer to above 50%.

Copolymerization of dienic hydrocarbons with vinyl ethers

1. n investigation was made of the emulsion and mass copolymerization of chloroprene with isopropyl vinyl ether at various temperatures. 2. n presence of initiators for radical copolymerization, two mechanisms operate simultaneously; a) copolymerization by the radical mechanism, and b) copolymerization by the cationic mechanism. 3. he relative amounts of copolymers of the radical and cationic types are considerably dependent on the polymerization conditions. Under all conditions the copolymer of the cationic type predominates. 4. Conditions were found which make it possible for the process to be directed in a single direction with formation of copolymers containing tip to 95–98% of the vinyl ether (molecular weight 60,000–90,000) or 80–90% of chloroprene (molecular weight 60,000). 5. The radical-copolymerization constants of the system were determined; r1 = 0.164± 0.043; r2 = 11.45 ± 0.54. The existence of two constants is explained as the result of the effect of the penultimate monomer unit (M2). 6. The emulsion copolymers corresponded in composition to a mechanism of radical copolymerization.

Formation of low-molecular-weight polymers of vinyl ethers in presence of benzoyl peroxide

1. The interaction of butyl and isopropyl vinyl ethers with benzoyl peroxide was studied at peroxide concentrations of 0.1–10%. 2. It was shown that at benzoyl peroxide concentrations of 2% and less, the vinyl ether polymerizes with formation of products of low molecular weight. At peroxide concentrations of 5% and 10%, addition and polymerization reactions occur simultaneously.

Polymerization of isopropyl vinyl and cyclohexyl vinyl ethers in presence of 2,2?-azobis[2-methylpropionitrile

1. A study was made of the free radical polymerization of cyclohexyl vinyl and isopropyl vinyl ethers in presence of 2,2′-azobis[2-methylpropionitrile]. 2. It was shown that the yields and molecular weights of the resulting polymers are dependent on the conditions of polymerization and the structure of the ether.

Polymerization of isopropyl vinyl and cyclohexyl vinyl ethers in presence of 2,2?-azobis[2-methylpropionitrilei

Polymerization of isopropyl vinyl and cyclohexyl vinyl ethers in presence of 2,2?-azobis[2-methylpropionitrilei

Synthesis of sulfur compounds by the aid of vinyl ethers and acetylene. Communication 8. General method for the synthesis of 2-alkoxyethanethiols

1. Reaction of hydrogen sulfide with ethyl, propyl, isopropyl, isobutyl, octyl, isopentyl, and eyclohexyl vinyl ethers yielded 2-talkoxyethaiethiols and mixtures of sulfides containing various proportions of the isomeric dialkoxy diethyl sulfides. Addition products formed in violation of Markovnikov's rule predominated in the reaction mixtures, particularly in the case of ethers having normal alkyl radicals. Ethers having branched (isopentyl) and cyclic (cyclohexyl) radicals gave particularly high yields of “normal” addition products. 2. A general method is given for the synthesis of 2-alkoxyethanethiols ROCH2,CH2SH in 55–80% yield from the corresponding vinyl ethers. 3. It is sugganti-Markovaikovsted that the ratio of Markovnikov and anti-Markovnikov addition products is related to the tendency of the vinyl ether to react by an ionic mechanism.