2-methyl-propenic acid

METHYL PROPENIC ACID, METHYL ESTER (80-62-6) CsHgOj Highly flammable, polymerizable liquid. Forms heat-sensitive explosive mixture with air [explosion limits in air (vol %) 1.8 to 12.5 flash point 50°F/10°C autoignition temp 790°F/421°C Fire Rating 3]. Unless inhibited, forms unstable peroxides heat or contaminants can cause explosive polymerization. Violent reaction with strong oxidizers benzoyl peroxide or other polymerization initiators. Elevated temperatures, light, contamination can cause... 

METHYL PROPENIC ACID (79-41-4) Combustible liquid (flash point 152°F/67°C oc). A reducing agent. Violent reaction with oxidizers, strong acids, alkalis. Unless inhibited (100 ppm of the monomethyl ether of hydroquinone is recommended), can polymerize violently. Polymerization can be caused by elevated temperatures, peroxides, sunlight, or hydrochloric acid. Incompatible with ammonia, amines, isocyanates, alkylene oxides, epichlorohydrin. Attacks metals, natural rubber, neoprene, nitrile, and some plastics including PVC and polyvinyl alcohol. The uninhibited monomer vapor may block vents and confined spaces by forming a solid polymer material. 

METHYL PROPENIC ACID, METHYL ESTER (80-62-6) Forms heat-sensitive explosive mixture with air (flash point 50°F/10°C). Unless inhibited, forms unstable peroxides. Violent reaction with strong oxidizers, benzoyl peroxide, or other polymerization initiators. 

FIGURE 6.9 Mechanism of acid-catalyzed hydration of 2-methyl propene. 

The initiator can be a radical, an acid, or a base. Historically, as we saw in Section 7.10, radical polymerization was the most common method because it can be carried out with practically any vinyl monomer. Acid-catalyzed (cationic) polymerization, by contrast, is effective only with vinyl monomers that contain an electron-donating group (EDG) capable of stabilizing the chain-carrying carbocation intermediate. Thus, isobutylene (2-methyl-propene) polymerizes rapidly under cationic conditions, but ethylene, vinyl chloride, and acrylonitrile do not. Isobutylene polymerization is carried out commercially at -80 °C, using BF3 and a small amount of water to generate BF3OH- H+ catalyst. The product is used in the manufacture of truck and bicycle inner tubes. 

Fig. 56. Dependence of Mwof the microgels on the polymer yield in the anionic polymerization of EDMA in toluene by n-BuLi [254] (see Figure 53 caption for the reaction conditions). Reduced viscosity vs concentration of microgels a) Composition (mol %) N,N -methyl-enebisacrylamide (55%), methacrylamide (33%), methacrylic acid (2%), methacrylamido acetaldehyd-dimethylacetal (10%),measured at 20 °C in water, b) Composition (mol %) 1,4-DVB (35%), propenic acid amide-2-methyl-N-(4-methyl-2-butyl-l,3-dioxolane prepared by emulsion copolymerization and measured in dimethylformamide.

Fig. 57. Diameters of microgels prepared with different emulsifier concentrations (SDS). Composition (mol %) NjN -tetramethylenebismethacrylamide (10%),N-n-hexylmethacrylamide, propenic acid amide-N-(4-methyl-2-butyl-l,3 dioxolane (50%)...

A microgel of a dz = 76 nm which is suitable for coupling with proteins, can be prepared by emulsion terpolymerization of NjAT -tetramethylene bisacrylamide, n-hexylmethacrylamide and propene acid amide-N-(4-methyl-2-butyl-1,3-diox-olane) [291 ]. The diameter of these microgels may be varied by the concentration of the emulsifier (Fig. 57) and is rather uniform. As the CMC of this system is about 2.5 X10"3 mol SDS/1, it may be assumed that below this value the copolymerization essentially takes place in the monomer droplets, whereas at higher concentrations of SDS preferentially the monomers in micelles are polymerized. 

Synonyms Acrylic acid, methyl ester AI3-15715 BRN 0605396 CCRIS 1839 Curithane 103 EINECS 202-500-6 Methoxycarbonylethene Methoxycarbonylethylene Methyl propenate Methyl propenoate Methyl-2-propenoate NSC 24146 Propenoic acid, methyl ester 2-Propenoic acid, methyl ester UN 1919. 

Kolbe noted also the formation of traces of methyl acetate and butyl valerate from electrolysis of acetate and valerate respectively. Careful analysis of reaction products by Petersen (1900) identified compounds which are today formulated as being derived from carbocations formed by loss of one electron from the alkyl radical [50]. Propanoic acid gives mostly ethene while butanoic acid and 2-methyl-propanoic acid give mostly propene. Acetate and long chain alkylcarboxylates give mostly the Kolbe type dimer hydrocarbon on electrolysis of their potassium salts in concentrated solution at a platinum electrode, using high current density and low temperatures [51]. 

In another paper from the Jackson Laboratories of the du Pont Company (Calcott et al., 34) there is reported a repetition of some of the reactions of Simons and Archer, as well as additional ones. Mono-, di-, and 1,2,4,5 tetraisopropylbenzene were obtained from propylene and benzene both l -chloro-i-butylbenzene and di-(l/-chloro)-d-butylben-zene were obtained from 3-chloro-2-methyl-propene-l and benzene p-f-butyltoluene and di-i-butyltoluene were obtained from diisobutylene and toluene tetraisopropylnaphthalene was obtained from propylene and naphthalene naphthyl-stearic acid was obtained from oleic acid and naphthalene mixed isopropyltetrahydronaphthalene was obtained from propylene and tetrahydronaphthalene 2,4,6-triisopropylphenol was obtained from propylene and phenol a mixture of monoisopropylated m-cresols was obtained from propylene and wi-cresol and di-(s-hexyl)-diphenyl oxide was obtained from hexene-3 and diphenyl oxide. 

Such reactions are used by the petroleum industry to produce medium-molecular-weight hydrocarbons from smaller molecules. A particularly important example is afforded by the addition of 2-methylpropane to 2-methyl-propene in the presence of sulfuric acid or anhydrous hydrogen fluoride to yield 2,2,4-trimethylpentane ... 

The fert-butyloxycarbonyl (BOC) group is cleaved using TFA in an aprotic solvent like CH2C12. The cleavage proceeds via protonation of the carbonyl group of carbamate 16, subsequent elimination of carbenium ion 58 and liberation of unstable free carbaminic acid 60 which breaks down yielding the unprotected indole 61 with loss of C02. Cation 58 is deprotonated giving 2-methyl propene 59. 

Methyl-tertiary-butyl ether (MTBE) is one of the leading chemicals currently being made from isobutylene (methyl propene) via the acid-catalyzed addition of methyl alcohol. MTBE has been added to gasoline as a required oxygenate. Eiowever, it is under attack as a groundwater contaminant and is being phased out. 

Enamines derived from aldehydes react with SchifFs bases in methanol in the presence of toluene-/ -sulphonic acid to yield tetrahydroquinolines thus l-morpholino-2-methyl-propene and benzylideneaniline afford 3,3-dimethyl-4-morpholino-2-phenyl-l,2,3,4-te-trahydroquinoline 238 (equation 100)123. 

METHYL ACRYLATE, INHIBITED pOT) METHYL PROPENATE METHYL PROPENOATE METHYL2-PROPENOATE METILACRILATO (ITALIAN) PROPENOIC ACID METHYL ESTER 2-PROPENOIC ACID METHYL ESTER... 

An economical procedure for the formation of r-butyl esters is the reaction of a carboxylic acid with 2-methyl propene in the presence of an acid catalyst. For a laboratory-scale preparation, formation of the mixed anhydride using MsCl in the presence of r-BuOH gives the ester in good yield. ... 

M ethy Icy clo hexano 1 ds-2-Methylcyclohexanol trans-2-Methylcyclohexanol Methylcyclopentane 1 - M ethy Icy clo p ent ene 3-Methylcyclopentene Methyldichlorosilane Methylethyl ether Methylethyl ketone Methylethyl sulfide Methyl formate Methylisobutyl ether Methylisobutyl ketone Methyl Isocyanate Methylisopropyl ether Methylisopropyl ketone Methylisopropyl sulfide Methyl mercaptan Methyl methacrylate 2-Methyloctanoic acid 2- M ethy lp ent ane Methyl pentyl ether 2- M ethy lp ro p ane 2- M ethyl- 2- p rop ano 1 2-Methyl propene Methyl propionate Methylpropyl ether Methylpropyl sulfide Methylsilane... 

METHYL PROPENATE (96-33-3) C4H 02 CHj=CHCOOCHj Forms explosive mixture with air (flash point 27°F/-3 C oc Fire Rating 3). Forms unstable peroxides when exposed to air in storage. Heat above 70°F/21°C, sunlight, contamination, and/or lack of appropriate level of inhibitor concentration can cause spontaneous, exothermic polymerization. Violent reaction with strong oxidizers. Incompatible with strong acids, alkalis, aliphatic amines, alkanolamines. Usually... 

PROPENIC ACID, 2-METHYL-, BUTYL ESTER (97-88-1) Forms explosive mixture with air (flash point 105°F/41°C). Unless inhibitor is maintained at the proper level, oxidizers, heat, UV light, or moisture may cause polymerization. Reacts with oxidizers. May accumulate static electrical charges may cause ignition of its vapors. 

The convenient synthesis of a-hydroxyl-co-methoxycarbonyl asymmetric telechelic PIBs has been achieved by the combination of two recently discovered techniques, haloboration-initiation and end capping with 1,1-diphenylethylene followed by end quenching with silyl ketene acetals, 1 -methoxy-1 -trimethylsiloxy-2-methyl-propene (MTSMP), 1-methoxy-1-trimethylsiloxy-propene (MTSP), and 1-methoxy-l-trimethylsiloxy-ethene (MTSE). Nearly quantitative chain end functionalization has been proved by NMR, quantitative NMR, and FT-IR spectroscopy. The methoxycarhonyl end arising by quenching with MTSMP could not be hydrolyzed under either basic or acidic conditions. These methods also failed to yield the acid when the corresponding diisobutylene derivative was used. The sterically less hindered esters, however, readily underwent hydrolysis resulting in the formation of a-hydroxyl-co-carboxyl asymmetric telechelic PIBs. 

Synonyms methyl-2-propenoate methyl propenate 2-propenoic acid methyl ester acrylic acid methyl ester... 

Clearly, the ethylene complex is more stable than the complexes with maleate and fiunarate. However, also methyl substituents, for example, 2-methyl-propene, form weaker complexes than ethylene. These residts suggest that for Cu(I), the n acidity and the a-donating properties of the ligand affect the stability constant of the complexes similarly and that steric hindrance contributes to the stability of these complexes. It is of interest to note that the complex of Cu(I) with acetylene belongs to the first group after the ligand loses a proton— Cu-C= CH (33)... 

A number of perfluoromethacrylic acid derivatives have been obtained by the elimination of alkyl fluoride from alkoxy-derivativesof perfluoro-(2-methyl propene) and related compounds for details describing the preparation and reactions of carbonyl derivatives of fluorinated olefins see Chapter 2, pp. 62—77. Fluoroalkyl acrylates, CH2 CH-C02Rf [Rf = (CF3)2CF, (CF3)(CF2C1)-CF etc.], have been... 

Alkenes lacking phenyl substituents appear to react by a similar mechanism. Both the observation of general acid catalysis and a solvent isotope effect are consistent with rate-limiting protonation with simple alkenes such as 2-methyl-propene and 2,3-dimethyl-2-butene. The observation of general acid catalysis rules out an alternative mechanism for alkene hydration, namely, water attack on an alkene-proton complex. The preequilibrium for formation of such a complex would be governed by the acidity of the solution, and so this mechanism would exhibit specific acid catalysis. 

The commercial production of f-butyl methyl ether has become important in recent years. In 2002, worldwide consumption of MTBE was about 7 billion gallons. With an octane value of 110, it is used as an octane number enhancer in unleaded gasolines. It is prepared by the acid-catalyzed addition of methanol to 2-methyl-propene. The reaction is related to the hydration of alkenes (Sec. 3.7.b). The only difference is that an alcohol, methanol, is used as the nucleophile instead of water. 

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