P-methyl acrolein

SYNS ALDEHYDE CROTONIQUE (FRENCH) trans-2-BUTENAL (E)-2-BUTENAL CROTONAL CROTONALDEHYDE CROTONIC ALDEHYDE 1,2-ETHANEDIOL DIPROPANOATE (9C1) ETHYLENE GLYCOL DIPROPIONATE (SCI) ETHYLENE PROPIONATE p-METHYL ACROLEIN NCI-C56279 PROPYLENE ALDEHYDE RCR.Y WASTE NUMBER U053 TOPANEL... 

Similarly, beta, b-, or P- indicates that the functional group is on the second carbon e.g., in P-methyl acrolein (CH3C2H2CHO) the methyl group (-CH3) is attached to the second carbon, the P-carbon, in the acrolein group, the first being attached to the aldehyde group (-CHO). 

Crotonic aldehyde 1,2-Ethanediol, dipropanoate Ethylene dipropionate 1-Formylpropene Methyl acrolein 3-Methylacrolein P-Methyl acrolein Propylene aldehyde Topanel Empiricai C4H6O Formuia CH3CH=CHCHO Properties Colorless to straw-colored mobile liq. pungent, suffocating, tar odor very sol. in ether, benzene sol. in DMSO, 95% ethanol, acetone, acid misc. with most org. solvs. sol. <0.1 mg/ml in water m.w. 70.09 sp.gr. 0.495 (25/4 C) vapor... 

Methyl acrolein 3-Methylacrolein p-Methyl acrolein. See Crotonaldehyde Methyl acrylate... 

The 6-0-benzyl protected dienes 4a and 4P were prepared from the known (10) 1,2-O-isopropylidene-a-D-glucofuranose (Scheme 3). In fhis case, evidence for the intermediate formation of aldehyde 23a in the Wittig reaction conducted at room temperature was obtained by comparison with an authentic sample of aldehyde 23a obtained directly from compound 21 (a + P) using P-tosyloxy acrolein prepaid in situ from the sodium salt of malonaldehyde and tosyl chloride in THF. Finally, the methyl substituted derivatives 5a and SP were prepared as for the parent dienes 2a and 2p according to Scheme 1 using the corresponding 2-methyl substituted sodium salt of malonaldehyde (72). 

Read ions of Heterocyclic Enamines with a,p-Unsaturated Compounds Enamines react readily with compounds containing a double bone activated by electronegative groups. Addition of acrolein to 1-methyl-2 ethylidenepyrrolidine, followed by dehydrogenation, leads to 1,7-dimethyl indole (133) (Scheme 9) (215). 

Similar cyclisations have also been invoked recently 159 160>. Support for our suggested mechanism is apparent from the structures of the products obtained with various methyl derivatives of acrolein. Similarly, p-deuteriocinnamaldehyde leads to 2-[2H]5.6,7,8-tetrachloroflavene 157>. 

In reactions in which methyl acrylate is used as the dienophile (Scheme 6.33), cycloadditions occur with lower levels of enantioselection (23% ee, as compared to 53 % observed for acrolein), but with significantly higher degrees of diastereoselectivity (17 1, endo-.exo). Improved levels of endo selectivity are observed in the case of the methyl ester (Scheme 6.33) this is perhaps because, at least in part, the dienophile p-system is oriented towards the t-butoxy ligand, where the steric influence of the bulky substituent is expected to be more pronounced. As before, formation of the endo isomer may occur to a greater extent, since the transition structure that leads to the exo isomer would involve energetically unfavorable interactions between the diene... 

CP 1309, see Pentachlorophenol CPD-244, see 2-Nittopropane CPD-926, see Dibenzofuran 4-CPPE, see 4-Chlorophenyl phenyl ether p-CPPE, see 4-Chlorophenyl phenyl ether Crag sevin, see Carbaryl Crawhaspol, see Trichloroethylene 2-Cresol, see 2-Methylphenol 4-Cresol, see 4-Methylphenol oCresol, see 2-Methylphenol p-Cresol, see 4-Methylphenol Crestoxo, see Toxaphene Crestoxo 90, see Toxaphene oCresylic acid, see 2-Methylphenol p-Cresylic acid, see 4-Methylphenol oCresyl phosphate, see Tri-ocresyl phosphate Crisalin, see Trifluralin Crisalina, see Trifluralin Crisfuran, see Carbofuran Crisulfan, see a-Endosulfan, p-Endosulfan Crisuron, see Diuron Crolean, see Acrolein Crop rider, see 2,4-D Crotenaldehyde, see Crotonaldehyde Crotilin, see 2,4-D Crotonal, see Crotonaldehyde Crotonic aldehyde, see Crotonaldehyde CRS, see Phenol Crunch, see Carbaryl Cryptogil OL, see Pentachlorophenol CS, see oChlorobenzylidenemalononitrile, Methyl mercaptan... 

Propylbenzene, see Propylbenzene Propyl carbinol, see 1-Butanol Propylene aldehyde, see Acrolein, Crotonaldehyde Propylene chloride, see 1,2-Dichloropropane Propylene dichloride, see 1,2-Dichloropropane a,p-Propylene dichloride, see 1.2-Dichloropropane 1,2-Propylene oxide, see Propylene oxide Propyl ester of acetic acid, see Propyl acetate Propylethylene, see 1-Pentene 5-Propylhexane, see 4-Methyloctane Propyl hydride, see Propane Propylic alcohol, see 1-Propanol Propyl iodide, see 1-Iodopropane n-Propyl iodide, see 1-Iodopropane Propylmethanol, see 1-Butanol Propyl methyl ketone, see 2-Pentanone n-Propyl nitrate, see Propyl nitrate... 

Free-radical-mediated four-component coupling reactions are rare. However, when an allyltin-mediated radical carbonylation is conducted in the presence of electron-deficient alkenes, four-component coupling reactions take place efficiently to give good yields of p-functionalized <5,fi-unsaturated ketones [40]. The wide scope of this four-component coupling reaction is noteworthy Primary, secondary, and tertiary alkyl bromides and iodides can be used as well as aromatic and vinylic halides. A variety of electron-deficient alkenes, such as methyl vinyl ketone, ethyl acrylate, acrolein, acrylonitrile, and vinyl sulfone, can be used as the acyl radical trap (Scheme 6.23). Fluorous allyltin compounds can also be used in four-component coupling reactions [41]. 

Hiickel MOs of acrolein are given on p. 254 and those of methyl acrylate in the previous exercise. 

For acrolein, styrene and methyl acrylate, see pp. 254, 264 and 268, respetively. 1-Hexene can be modeled by propene (p. 264). Ethyl vinyl ether can be modeled by methyl vinyl ether, enol or even propene. 

Intermediate A reacts with conjugated carbonyl compounds to give 1 1 adducts (92). Reaction of the intermediate produced from p-tolylpenta-methyldisilane with methyl vinyl ketone affords 2-trimethylsilyl-4-methyl(methylallyloxydimethylsilyl)benzene in 51% yield as the sole volatile product. Acrolein also reacts with phenylpentamethyldisilane under similar photolysis conditions to give 2-trimethylsilyl-4-methyl(allyloxydi-... 

ZnCh catalyzed ene reaction of methyl vinyl ketone and acrolein with p-pinene in ether at 25 C gives the expected ene adducts in 62% and 32% yields, respectively. Methyl vinyl ketone is reported to undergo AICI3 catalyzed ene reactions with limonene, carvone and perillaldehyde. Although Lewis acid catalyzed ene reactions of acrolein and methyl vinyl ketone with alkenes are probably general, the initial products often cannot be isolated since the unsaturated carbonyl compound undergoes an intramolecular Lewis acid catalyzed type II ene reaction. ... 

Lewis acid complexes of -substituted a, 3-unsaturated ketones and aldehydes are unreactive toward alkenes. Crotonaldehyde and 3-penten-2-one cannot be induced to undergo ene reactions like acrolein and methyl vinyl ketone. The presence of a substituent on the -carbon stabilizes the enal- or enone-Lewis acid complex and stericdly retards the approach of an alkene to the -carbon. However, Snider et al. have found that a complex of these ketones and aldehydes with 2 equiv. of EtAlCk reacts reversibly with alkenes to give a zwitterion (22). This zwitterion, which is formed in the absence of a nucleophile, reacts reversibly to give a cyclobutane (23) or undergoes two 1,2-hydride or alkyl shifts to generate irreversibly a p, -disubstituted-a,P-unsaturated carbon compound (24). 

Just as trialkylboranes add to simple alkenes (15-16), they rapidly add to the double bonds of acrolein, methyl vinyl ketone, and certain of their derivatives in THF at 25°C to give enol borinates (also see, p. 631), which can be hydrolyzed to aldehydes or ketones." If water is present in the reaction medium from the beginning, the reaction can be run in one laboratory step. Since the boranes can be prepared from alkenes (15-16), this reaction provides a means of lengthening a carbon chain by three or four carbons, respectively. Compounds containing a terminal alkyl group, such as crotonaldehyde (CH3CH=CHCHO) and 3-penten-2-one, fail to react under these conditions, as does acrylonitrile, but these compounds can be induced to react by the slow and controlled addition of O2 or by... 

The reaction did not require dry solvents or inert atmosphere and afforded the desired adducts in 42-98% yield. As expected, the more reactive acrolein and methyl vinyl ketone gave very good results with both acyclic and cyclic p-ketoesters and p-diketones and, surprisingly, acrylonitrile and methyl acrylate, reported to be totally inactive under Lewis acid catalysis, " afforded the corresponding adducts with a-acetylbutyrolactone in high yield (77 and 98% respectively). In the reaction with crotonaldehyde, a 1 1 mixture of... 

Access to key materials for synthesis in this group has been possible for some years by reaction of acrolein with 2-methyl-3-pentanone in presence of p-toluenesulfonic acid, distilling off the water formed during the reaction, and leading to 2,6,6-trimethyl-2-cyclohexenone (690). Alternatively, 2-methyl-3-pentanone reacts with methyl acrylate in the presence of base (sodium methoxide/ methanol in xylene) to give 92% of the diketone 691 (probably as the enol). ... 

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