5- Methyl-2-cyclohexenyl acetate

Reaction with an aUylic acetate. The reaction of cis- and rra j-5-methyl-2-cyclohexenyl acetate, (1) and (2), with this cuprate is highly stereoselective. Experiments with deuterium-labeled (1) and (2) show involvement of a symmetrical intermediate in which the two allylic positions arc equivalent. ... 

The conversion of cis- and /ra j -5-methyl-2-cyclohexenyl acetate (63) into 3,5-dimethylcyclohexene (64) with Me2CuLi is stereospecific, the substitution occurring on the side of the ring opposite from the replaced acetate group. ... 

Fig. 97. Solvent retained by nitrocellulose films (50/i thickness) after exposure to air at 25°C (Baelz [48]). I—Cyclohexenyl acetate, II—methyl cyclohexanone, III—diacetone alcohol, IV—cyclohexanone, V—cellosolve acetate, VI—amyl acetate-ethyl alcohol I 1, VII—amyl acetate, VIII— methyl cellosolve acetate, IX—amyl acetate-toluene 1 1, X—butyl acetate-ethyl alcohol 1 1, XI—butyl acetate, XII—cellosolve, XIII—methyl-ethyl ketone, XIV—cellosolve-toluene 1 1, XV—methyl cellosolve, XVI—ethyl acetate, XVII—acetone.

Trimethyl-1-cyclohexen-1-yl)-4-penten-3-one 5-(2,6,6-Trimethyl-1-cyclohexenyl)-4-penten-3-one. See Methyl p-ionone 5-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-4-penten-3-one 5-(2,6,6-Trimethyl-2-cyclohexenyl)-4-penten-3-one. See Methyl a-ionone 5-(2,6,6-Trimethyl-3-cyclohexen-1-yl)-4-penten-3-one. See Methyl A-ionone Tri methyl cyclohexyl acetate CAS 67859-96-5... 

In addition to allylation by the usual nucleophihc attack at the terminal carbon of allylic systems, substituted cyclopropanes are formed by the attack of a nucleophile at the central sp carbon of the allylic systems via palladacyclobutane under certain conditions. " Cyclopropanation can be understood by the attack of the enolate ion at the central carbon of TT-allylpalladiuin to form palladacyclobutane, followed by reductive elimination (Scheme 17). 2-Cyclohexenyl acetate reacts with the ketene silyl acetal of methyl acetate using the Pd catalyst coordinated by dppp, to afford cyclopropane and the expected methyl 2-cyclohexenylacetate. Cyclopropanation becomes the main path when TMEDA as a ligand and thallium acetate are added. 

Isopropenyl, 3-( l-cyclohexenyl)-acetate 0.57 0.66 Vinyl methyl sulfoxide 0.60 - 1.79... 

Electrochemical fluorination of a-cyclohexenyl-substituted carboxylic (acetic, propanoic, butanoic, and pentanoic) acid esters (methyl, ethyl, and propyl) results in a series of both perfluoro-9-alkyl-7-oxabicyclo[4 3 OJnonanes and per-fluoro-8-alkoxy-9-alkyl-7-oxabicyclo[4.3.0]nonanes [<8S] (equation 19)... 

Potassium or lithium derivatives of ethyl acetate, dimethyl acetamide, acetonitrile, acetophenone, pinacolone and (trimethylsilyl)acetylene are known to undergo conjugate addition to 3-(t-butyldimethylsiloxy)-1 -cyclohexenyl t-butyl sulfone 328. The resulting a-sulfonyl carbanions 329 can be trapped stereospecifically by electrophiles such as water and methyl iodide417. When the nucleophile was an sp3-hybridized primary anion (Nu = CH2Y), the resulting product was mainly 330, while in the reaction with (trimethylsilyl)acetylide anion the main product was 331. 

Acetic acid, butyl ester Acetic acid, pentyl ester Acetic acid, decyl ester Acetic acid, benzyl ester Acetic acid, benzyl ester Acetic acid, 1-cyclohexenyl ester Acetic acid, 3-cyclohexenyl ester Butyric acid, benzyl ester Phenylacetic acid, propyl ester Oleic acid, methyl ester Linoleic acid, methyl ester Linolenic acid, methyl ester Adipic acid, methyl ester Adipic acid, ethyl ester Adipic acid, diethyl ester Adipic acid, dipropyl ester Adipic acid, (methylethyl)ester Adipic acid,... 

Chloro-5-(l -Cyclohexenyl)-l-Methyl-2-Oxo-2,3-Dihydro-lH-Benzo[f]Diazepine-l,4 9.7 grams of sodium methylate are added to a solution of 16.5 grams of 7-chloro-5-(l -cyclohexenyl)-2-oxo-2,3-dihydro-lH-benzo[f]diazepine-l,4 dissolved in 120 ml of dry dimethylformamide and the mixture stirred for one-half hour. The reaction mixture is cooled in a water bath and a solution of 33.8 grams of methyl iodide dissolved in 35 ml of anhydrous dimethylformamide is then slowly added with stirring. The solution becomes dark brown in color and a precipitate forms. It is stirred for 2 hours, then diluted with a large volume of water and extracted with ethyl acetate. 

To quantitatively understand the preference for the chairlike and boathke transition states of the Claisen rearrangement, Houk et al. carried out a computational study12 (Scheme l.VIII). In the theoretical treatment two methyl acetals, 7Z(OMe) and 7/ (()Me), were used as a model system instead of the fert-butyl-dimethylsilyl (TBS) ketene acetal. Calculations locate four transition states for the rearrangement of 7Z(OMe), among which boathke transition state A is of the lowest energy that leads to the formation of the major isomer observed experimentally. Chairlike transition state B is disfavored, due to steric repulsion between the axial hydrogen of the cyclohexenyl unit and the methoxy substituent of the alkene. 

Neat A-(l -methyl-4-pentenyl)hydroxylamine underwent facile cyclization to the corresponding Y-hydroxypyrrolidine 1 on wanning briefly to 50- 60 °C, via a radical chain reaction involving the nitroxide radical. A-(l-Methyl-5-hexenyl)hydroxylamine cyclized to give A-hydroxypipe-ridine 2 only in refluxing xylene under high dilution conditions, this is necessary to avoid formation of byproducts. The cyclization was facilitated by the presence of a-methyl substituents in the hydroxylamine. Transannular cyclization of A-[(3-cyclohexenyl)methyl]hydroxylamine was not successful. Since the isolation of pure samples of the water-soluble and easily oxidized hydroxylamines was not a satisfactory procedure, the crude reaction mixtures were subjected to reduction with a zinc/acetic acid/acetic anhydride system to isolate acetylated cyclic amines. 

In early investigations, treatment of the magnesium complex of 1,2-dimethylenecyclohexane 2 with ethyl acetate at low temperature ( — 78 to — 10°C), and then quenching the reaction at —10 C, resulted in the formation of (2-methyl-l-cyclohexenyl)propan-2-one in 72% isolated yield. On the other hand, warming the mixture to reflux, followed by workup, afforded a fused bicyclic enol, 2,3,4,5,6,7-hexahydro-2-methyl-l//-inden-2-ol in excellent... 

Treatment of methyl 2-benzoyl-2-cyclopropyl-3-iodopropanoate with chromium(II) acetate in acetonitrile afforded a mixture of cyclohexenyl and cyclohexadienyl esters (Section 2.4.1.5.9.). 

The 4-methoxy group present in the des bases C and D may be present in tazettine itself or introduced in the course of the methylation with dimethyl sulfate. Kondo and co-workers preferred the latter alternative they formulated tazettine as an enol which was converted to an enol methyl ether in the preparation of methyltazettine methiodide. Such a concept is inadmissible since 0-acetyltazettine does not have the spectral or chemical properties of an enol acetate. Further, the hydrolytic conditions required to convert methyltazettine methochloride to tazettine methochloride (in poor yield) were more vigorous than those usually required for the hydrolysis of a 1-cyclohexenyl methyl ether. It is evident then that the methoxyl group of tazettine is in the 4-position of CXXV, and it follows that the double bond is located in the 2,3-position. 

Cycloalkenes can also be acylated with aluminum chloride or tin tetrachloride as catalyst 627,628 cycloheptene, acetyl chloride, and aluminum chloride give 70% of 1-cycloheptenyl methyl ketone.629 The yield from cyclohexene and phenylacetyl chloride is, however, below 30% but better yields are obtained with acetyl chloride and zinc chloride (60% of 1-cyclohexenyl methyl ketone630,631) or acetic anhydride and tin tetrachloride.632... 

The kinetics of solvolysis of optically active cis- and /raAZ5-5-methyl-2-cyclohexenyl chlorides provides additional insight into the ion-pair internal return mechanism of allylic isomerization. Solvolysis of both of these chlorides in ethanol and acetic acid is accompanied by loss of optical activity without cis-trans isomerization of the unreacted chloride [(12), Y = C1]. The fact that rate of loss of optical activity exceeds rate of formation of solvolysis products provides evidence for internal return from carbonium chloride ion pairs, unaccompanied by geometrical isomerization. This conclusion is supported by the observation that the ratio of racemization rate to solvolysis rate is insensitive to added ionic chloride. 

In protic solvents, the allylic carbonium ion formed by acid-catalyzed alkyl carbon-oxygen bond fission can recombine either with the carboxylic acid molecule or with a solvent molecule. The electrostatic attraction between the carbonium and carboxylate ions, which is a major factor in isomerization of allylic esters by ion-pair internal return during solvolysis, is absent in the acid-catalyzed reaction. The more numerous, usually more nucleophilic, solvent molecules in the solvation shell of the carbonium ion should compete effectively with the departed carboxylic acid molecule and solvolysis rather than isomerization should be the predominant reaction. For example, in the presence of 0.05 M perchloric acid, solvolyses of cis- and //- //7.s-5-methyl-2-cyclohexenyl p-nitrobenzoates are not only very much faster than in the absence of the acid, but polarimetric and titrimetric rates of solvolysis of optically-active esters were identical within experimental error. For these esters, the acid-catalyzed solvolysis was not accompanied by a detectable amount of isomerization. Braude reported, on the basis of indirect evidence, that isomerization accompanies acid-catalyzed hydrolysis of a-ethynyl-y-methylallyl acetate in aqueous dioxane. It was shown that, under some experimental conditions, the spectrophotometrically determined rate of appearance of the rearranged 1 -yne-3-ene chromophore exceeds the titrimetrically determined rate of hydrolysis,... 

Dicyanoethylene. See Fumaronitrile Dicyanogen. See Cyanogen Dicyanomethane. See Malononitrile 1,3-Dicyanotetrachlorobenzene 1,3-Dicyano-2,4,5,6-tetrachlorobenzene. See Tetrachloroisophthalonitrile 3,9-Di (3-cyclohexenyl)-2,4,8,10-tetraoxaspiro (5,5) undecane. See Pentaerythrityl-bis-tetrahydrobenzaldehyde acetal Dicyclohexiamine, N-methyl-. See N-Methyldicyclohexylamine Dicyclohexylamine... 

Features Bergamot oil with lemon top note Trade Name Synonyms CItryl Acetate 3/022401 [Dragoco http //www.dragoco.com, http //www.symrise.com] 2-(4-Methyl-3-cyclohexenyl)-2-propanol CAS 99-55-5 EINECS/ELINCS 202-680-6 Uses Fragrance ingred. as chem. intermediate precursor of a-terpineol Trade Name Synonyms Terpineol 350 [Millennium/F F http //www.aromachem.com]... 

Kola (Cola acuminata) extract astringent, skin treatment Zinc oxide astringent, toners Kola (Cola acuminata) extract astringent, topical Aluminum chloride hexahydrate astringent, topical hexahydrate Aluminum chloride anhydrous astringent, veterinary medicine Lead acetate trihydrate asymmetric epoxidation, transition metal catalyzed trans-Stilbene a-terpineol precursor 2-(4-Methyl-3-cyclohexenyl)-2-propanol atmosphere protectant, casting magnesium alloys... 

Lemon (Citrus medica limonum) oil Lime (Citrus aurantifolia) extract Maltyl acetate Maltyl butyrate Maltyl isobutyrate Marjoram (Thymus mastichina) oil o-Methylanisole -o-M ethyl benzyl acetate 2-Methylbutyl acetate Methyl 2-butyl butyrate Methyl-2-butyl-2-methylbutyrate Methyl p-t-butylphenylacetate DL-2-Methylbutyric acid Methyl caprate Methyl caproate Methyl caprylate 2-(4-Methyl-3-cyclohexenyl)-2-propanol 4-(1-Methylethyl) cyclohexadiene-... 

Cyclododecyl acetate Cyclododecyl formate 5-Cyclohexadecen-1 -one Cyclohexanecarboxylic acid Cyclohexanone diethyl acetal Cyclohexanone, 4- [(3,3-dimethylbicyclo [2.2.1] hept-2-yl) methyl]-2-methyl- 2-Cyclohexenyl cyclohexanone Cyclohexyl acetate Cyclohexyl butyrate Cyclohexyl crotonate Cyclohexylcyclohexanone Cyclohexyl cyclopenteneacetate... 

Sol 1. (d) Abstraction of proton from a-methyl group of ester and subsequent treatment with trimethylsilyl chloride (TMSCl) resulted in the formation of cyclohexenyl silyl ketene acetal, which on heating undergoes [3,3] shift, i.e., Ireland—Claisen (silyl ketene acetal) rearrangement. The final step is the removal of the silyl group by acid hydrolysis to get the free acid. 

Methylcyclohexanone diethyl acetal heated with 0.1% anhydrous p-toluenesulfonic acid at 100-110° under ca. 100 mm pressure with distillation of the resulting ethanol 4-methyl-1-cyclohexenyl ethyl ether. Y 82%. F. e. s. U. Schmidt and P. Grafen, A. 656, 97 (1962). 

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