4- -phenyl -2-methyl-propen

The addition of the anion of the racemic 2-methyl-2-propenyl sulfoxides, rac-2-methyl-3-(phenyl-sulfinylpl-propene and /w-3-(rerr-butylsulfinyl)-2-methyl-l-propene to 2-cyclopentenone gives mixtures of (E)- and (Z )-y-l, 4-addition products which are a mixture of diastereomers at sulfur2. The (T )-products usually predominate, with the relative proportions of the (Z)-product increasing as the reaction temperature is increased. No asymmetric induction originating from the stereocenter at sulfur was observed when the sulfoxide substituent was phenyl however, there was a marginal improvement in the case of the (Zi)-product when the sulfoxide substituent was ferf-butyl. 

Benzylchlorid 1-Chlor- l-phenyl-athan Chlor-diphenyl-methan Dichlor-phcnyl-mcthan D ichlor- diphenyl- methan 3-Chlor-2-methyl-propen... 

The development of Ir-chiral N,P ligand system opens another promising way for the hydrogenation of allylic alcohol and its derivatives. For example, a cationic Phox-Ir complex catalyzes the hydrogenation of ( )-2-methyl-3-phenyl-9-propen-l-ol in a highly enantioselective fashion.178 With 1 mol.% (5)-92-Ir catalyst, the hydrogenation proceeds completely to provide the chiral alcohol product in 96% ee. Under the same conditions, a para- Bu-substituted chiral alcohol derivative is obtained with 94% ee for the synthesis of lilial (Equation (59)). Heterocyclic N, P-ligand, HetPHOX 113, is also efficient for this reaction.191... 

CH3)2C=CHCH2CH2CHO + CeH5CH=CHCH2OH 5-methyl-4-hexenal 3-phenyl-2-propen-1-ol... 

Acetophenone and magnesium methyl iodide yield 2-phenyl-l-propene. As can be seen from the equation, one at least of the radicals R, R1 Ru, must have a non-tertiary carbon linked in the intermediate compound to the hydroxy-magnesium-iodide carbon. 

A cationic Ir complex possessing phosphanodihydrooxazole 26 is usable for asymmetric hydrogenation of allylic alcohols. (E)-2-Methyl-3-phenyl-2-propen-l-ol can be converted in CH2C12 containing 1 mol % of the Ir complex to the saturated product in 95% yield and 96% ee (Scheme 1.26) [141]. The process is used in the enantioselective synthesis of the artificial fragrance filial. 

Basic alumina (13 g) was added to a mixture of methyl 4-formylbenzoate Id (1.00 g, 6 mmol) and acetophenone 2 (0.48 g, 4 mmol) at room temperature. (When the reactants were solid, a minimum amount (2x3 mL) of dichloro-metliane was used to dissolve them prior to the addition of the alumina.) The reaction mixture was then agitated at room temperature for 2.5 h using a Fisher vortex mixer. The product was extracted into dichloromethane (5x15 mL). Removal of the solvent, under reduced pressure, yielded the solid product. Further purification (removal of traces of benzyl alcohol and aldehyde) was carried out by recrystallization from a petroleum ether-ether mixture to afford l-phenyl-3-[4-(carbomethoxy)phenyl]-2-propen-1-one 3d (4-carbomethoxychalcone), mp 119— 120 °C (81%). 

Finally, the last uncertain case concerns the prevailing isomer arising from hydrocarbalkoxylation of (E)-l-phenyl-l-propene. In this case practically none of the predicted prevailing isomer 2-methyl-3-phenylpropanoate is formed. However, the prevailing ester (55%) is not the other expected isomer (2-benzylpropanoate) but rather the 4-phenylbutanoate which arises from isomerization of either the substrate ((E)-1-phenyl-1-propene to 3-phenyl-l-propene) or the catalyst-substrate complex. 

The results concerning the enantiomeric excess for 1-pentene show that quadrant Q 2 is preferred to quadrant Q t, as predicted both for Pt/(—)-DIOP and Rh/ (—)-DIOP catalytic systems. Furthermore, with Pt/(—)-DIOP, quadrant Q2 is preferred to quadrant Qt, as predicted, whereas with Rh/(—)-DIOP, quadrant Qt is preferred to quadrant Q2, in agreement with the results obtained with aliphatic 1,1-disubstituted ethylenes. Comparing the results obtained with a-[2H]-styrene and with 2-phenyl-1-propene it appears that the phenyl group prefers quadrant Qt (as the n-propyl group in 1-pentene) when 2H is in quadrant Q2 however, if a methyl group is present, steric repulsion is minimized when methyl occupies quadrant Qt and the phenyl group is in quadrant Q2. 

To a 2 L, 3-neck Morton flask fitted with a thermometer, a mechanical stirrer, and an addition funnel was added the methyl 3-hydroxy-2-methylene-3-phenylpropionate (305.9 g, 1.585 mol) followed by addition of 48% HBr (505 ml, 4.46 mol) in one portion. The flask was immersed in an ice-water bath, at which time concentrated sulfuric acid (460 ml, 8.62 mol) was added dropwise over 90 min and the internal temperature of the reaction mixture was maintained at 23°-27°C throughout the addition process. After removal of the ice-water bath, the mixture was allowed to stir at room temperature overnight. The solution was then transferred to a separatory funnel and the organic layer was allowed to separate from the acid layer. The acids were drained and the organic layer was diluted with 2 L of a 1 1 ethyl acetate/hexane solution, washed with saturated aqueous sodium bicarbonate solution (1 L), dried over sodium sulfate, and concentrated to yield 400.0 g (99%) of the desired (Z)-l-bromo-2-carbomethoxy-3-phenyl-2-propene as a light yellow oil, which was used without any additional purification, boiling point 180°C (12 mm). 

The acetyl-methyl group in 2-acctylphenyl methyl tellurium condenses with benzaldehyde to give methyl 2-(3 -phenyl-2 -propen-l -oyl)phenyl tellurium3. 

Methyl 2-(3 -Phenyl-2 -propen-r-oyl)phenyl Tellurium3 A stirred mixture of 12 g (46 mmol) of 2-acetylphenyl methyl tellurium, 17.6 m/(18.4 g, 170 mmol) of benzaldehyde, 88 mlof acetic acid, and 35 ml of piperidine is heated under reflux for 6 h. The mixture is then steam-distilled to remove unreacted benzaldehyde. The resultant red oil is separated by extraction with chloroform, the extract is evaporated, and the residue is fractionally distilled under vacuum. The fraction boiling above 200°/0.1 torr is collected and redistilled to give a condensate that should solidify. This solid is recrystallized several times from a mixture of petroleum ether and benzene yield 3.2 g (20%) m.p. 102-104° (from heptane/benzenc). 

The 2-methyl-3-phenylpropanal is 90% pure by GLC. The product mixture contains 6% of another isomer, 2-methyl-2-phenylpropanal, and a small amount of 2-phenyl-2-propen-l-ol. A completely pure sample of the aldehyde is readily obtained by stirring the crude aldehyde with excess saturated aqueous sodium bisulfite solution for several hours, filtering the solid bisulfite adduct, washing with ether, and liberating the aldehyde with excess aqueous sodium bicarbonate. Redistillation gives the completely pure aldehyde in about 60% yield. 

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. 

Benzyl-2-propen- IX, 504 2-Methyl-3-phenyl-2-propen- IX, 504 Thiokohlensaure -S-benzylester-O-... 

SYNS CHALCONE, 4-METHYL-(6CI,7CI,8CI) (4-METHYLBENZYLIDENE)ACETOPHENONE p-METHYLCHALCONE 3-(4-METHYLPHENYL)-l-PHENYL-2-PROPEN-1-ONE PHENYL p-METHYLSTYRYL KETONE 2-PROPEN-l-ONE,3-(4-METHYLPHENYL)-1-PHENYI ... 

SYNS FEMA No. 2697 METHYL CINNAMIC ALDEHYDE a-METHYLCINNAMIC ALDEHYDE O-METHYLCINNIMAL 2-METHYL-3-PHENYL-2-PROPENAL... 

METHYL-3-PHENYL-2-PROPENAL see MIOOOO xMETHYL-3-PHENYLPROPENOATE see MI0500... 

C10H10O 2-methyl-3-phenyl-2-propenal 101-39-3 521.15 45.920 1,2 19181 Cl OH1003 methyl benzoylacetate 614-27-7 538.15 47.561 2... 

C10H12O trans-2-methyl-3-phenyl-2-propen-1-ol 1504-55-8 502.76 44.150 2 19610 C10H12O2 4-propyl benzoic acid 2438-05-3 504.61 44.327 2... 

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