2-Methyl crotonic acid

SYNS 2-BUTENOIC ACID, 2-METHYL-, (E)-(9CI) CEVADIC ACID CROTONIC ACID, 2-METHYL-, (E)- (E)-2,3-DIMETHYLACRYLIC ACID trans-O-P-DIMETH-YLACRYLIC ACID trans-2,3-DIMETHYLACRYLIC ACID ttans-2-METHYL-2-BUTENOIC ACID (E)-2-METHYL-CROTONIC ACID trans-2-METHYLCROTOKIC ACID TIGUNIC ACID... 

Crotonic acid, ethyl ester. See Ethyl crotonate Crotonic acid, 2-methyl-, (E)-. See Tiglic acid Crotonic acid, methyl ester, (E)- (E)-Crotonic acid methyl ester. See Methyl crotonate Crotonic acid, 2-methyl-, ethyl ester, (E)-. See Ethyl tiglate... 

Crotonic acid, 2-methyl-, hexyl ester, (E)-. See Hexyl tiglate... 

CAS 16930-96-4 EINECS/ELINCS 240-997-1 Synonyms 2-Butenoic acid, 2-methyl-, hexyl ester, (E)- Crotonic acid, 2-methyl-, hexyl ester, (E)- N-Hexyl trans-2-methyl-2-butanoate ... 

Methylacrylic acid. See Crotonic acid a-Methylacrylic acid. See Methacrylic acid P-Methylacrylic acid. See Crotonic acid 2-Methyl-acrylic acid benzyl ester. See Benzyl... 

Methyl-2-cyclohexen-l-one 2-Cyclohexen-l-one, 3-methyl- (8,9) (1193-18-6) (E)-Methyl crotonate. Crotonic acid, methyl ester, (E)- (8), 2-Butenoic acid, methyl ester, (E)- (9) (623-43-8)... 

Fig. 1.31. The Wohl-Ziegler bromination of crotonic acid methyl ester D exclusively supplies the bromocrotonic ester G. However, vinyl acetic acid ester C and NBS exclusively yield the dibromo addition product B under Wohl-Ziegler conditions. Here, NBS acts as a Br2 source for addition rather than substitution. The fact that vinyl acetic acid ester and NBS do not react likewise to yield the bromocrotonic ester G is due to an electronic effect discussed in the text.

With fram-crotonic acid methyl ester, dimethylsulfoxonium methylide forms a cyclopropane stereoselectively (Figure 9.3, bottom). Therein, the methyl group and the COzMe group retain the trans orientation they had in the crotonic ester. Thus, the fnms-crotonic ester is cyclopropanated with complete retention of the configuration. 

Fig. 9.3. The pair of reactions illustrates the occurrence of stereoselectivity and the lack of stereospecificity in two cyclopropanations with an S ylide. The trans-crotonic acid methyl ester reacts with complete retention of the configuration, whereas the di-crotonic acid methyl ester reacts with complete inversion.

In addition to the above-mentioned monomers, various acrylic and methacrylic esters, methacrylonitrile, itaconic acid, crotonic acid, methyl vinyl ketone, allyl alcohol, allyl amine etc., have been studied by Fischer... 

C5H7CIO2 2-chloro-tra s-crotonic acid methyl ester 22038-57-9... 

C5 H7 Cl 02 3-chloro-trans-crotonic acid methyl ester 6214-25-1... 

Methyl crotonate. Purify commercial crotonic acid by distiUing 100 g. from a 100 ml. Claisen flask attached to an air condenser use an air bath (Fig. II, 5, 3). The pure acid passes over at 180-182° and crystallises out on cooling, m.p. 72-73° the recovery is about 90 per cent. Place 75 g. of absolute methyl alcohol, 5 g. (2 -7 ml.) of concentrated sulphuric acid and 50 g. of pure crotonic acid in a 500 ml. round-bottomed flask and heat under reflux for 12 hours. Add water, separate the precipitated ester and dissolve it in ether wash with dilute sodium carbonate solution until effervescence ceases, dry with anhydrous magnesium sulphate, and remove the ether on a water bath. Distil and collect the methyl crotoiiato at 118-120° the yield is 40 g. 

Chemically, wood tar is a complex mixture that contains at least 200 individual compounds, among which the foUowing have been isolated (1) 2-methoxyphenol, 2-methoxy-4-ethylphenol, 5-meth5i-2-methoxyphenol, 2,6-x5ienol, butyric acid, crotonic acid, 1-hydroxy-2-propanone, butyrolactone, 2-methyl-3-hydroxy-4JT-pyran-4-one, 2-methyl-2-propenal, methyl ethyl ketone, methyl isopropyl ketone, methyl furyl ketone, and 2-hydroxy-3-methyl-2-cyclopenten-l-one. 

C Nuclear magnetic resonance spectrum, acetaldehyde, 732 acetophenone, 732 anisole, 672 benzaldehyde, 732 benzoic acid, 771 p-bromoacetophenone, 449 2-butanone, 449, 732 crotonic acid. 771 cyclohexanol, 634 cyclohexanone, 732 ethyl benzoate, 477 methyl acetate, 443 methyl propanoate, 450 methyl propyl ether, 672... 

Acrylic acid (AA) and methacrylic acid (MAA) (purchased from Merck) are freed from inhibitor on a neutral aluminium oxid column and distilled. Acrylamide (AM) from Kebo, Stockholm, is recrystallized once from chloroform solution before use. Other monomers of analytical grade were purchased from Merck and used as received crotonic acid (CA), tiglic acid (TA), 3-methyl crotonic acid (3-MCA), and a-methyl cinnamic acid (oi-MCia) (Table 1). Benzophenone (analytical grade, Kebo) and acetone (spectroscope grade, Merck) were used as supplied. 

Drying in an evacuated desiccator over P2O5 removes water as well as methyl (R)-3-hydroxybutanoate and crotonic acid. 

Figure 11.11 Pyrogram of a paint sample collected from a decorative frame of the Universal Judgement by Bonamico Buffalmacco (fourteenth century, Monumental Cemetery of Pisa, Italy). Pyrolysis was performed with a microfurnace pyrolyser, at 600°C, in the presence of HMDS. 1, Benzene 2, ethyl acrylate 3, methyl methacrylate 4, acetic acid, trimethyl silyl ester 5, pyrrole 6, toluene 7, 2 methylpyrrole 8, 3 methylpyrrole 9, crotonic acid 10, ben zaldehyde 11, phenol 12, 2 methylphenol 13, 4 methylphenol 14, 2,4 dimethyl phenol 15, benzyl nitrile 16, 3 phenylpropionitrile 17, indole 18, phthalate 19, phthalate 20, ben zyl benzoate HMDS pyrolysis products [27]...

The reaction with hydroxide ion is frequently used as proof for the chemical structure of cyclopropenones and has been examined in some detail with respect to the factors governing ring-cleavage. Thus, methyl cyclopropenone23 and aqueous NaOH react to yield a mixture of methacrylic and crotonic acids in a ratio of 3 1 as expected from the relative stabilities of the two possible intermediate carbanions (type 317) ... 

Substrates 4-9 were chosen by Freeman to study the influence of steric bulk on the free activation energy. As discussed before the substituents also show an electronic effect and it is hard to separate both effects, but at least some comparisons can be made, e.g., for trans-crotonic acid 4 and 4,4-dimethyl-trans-2-pentenoic acid 9. The steric bulk of the t.-butyl group compared to a methyl group should be by far more important than the difference in the electronic effect. 

DIHYDROFURAN DIVINYL ETHER METHACROLEIN 2-BUTYNE-1,4-DIOL ganna-BUTYROLACTONE cis-CROTONIC ACID trans-CROTONIC ACID METHACRYLIC ACID METHYL ACRYLATE VINYL ACETATE ACETIC ANHYDRIDE SUCCINIC ACID DIGLYCOLIC ACID MALIC ACID TARTARIC ACID n-BUTYRONITRILE ISOBUTYRONITRILE ACETONE CYANOHYDRIN... 

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