3- Methyl-5-phenylpentanal

In the presence of alkah metals such as potassium and sodium, toluene is alkylated with ethylene on the methyl group to yield, successively, normal propylbenzene, 3-phenylpentane, and S-ethji-S-phenylpentane (21). 

Phenyl isocyanate, with ethyl hydrazine-carboxylate to give 4-phenyl-l-car-bethoxysemicarbazide,51,122 Phenylmercuric acetate, with methallyl alcohol to yield 2-methyl-3-phenyl-propionaldehyde, 51, 17 1-PHENYL-1,3-PENTADIYNE, 50, 97 1-PHENYL-1,4-PENTADIYNE. 50, 97 a-Phenylpentanal, from 2-benzyl-4,4,6-trimethyl-5,6-dihydro-l,3(4H)-... 

The methyl group in the y-position of the side-chain interferes with cyclization. The rate of C5-cyclization of n-butylbenzene at 371°C over platinum-on-silica gel is 3.5 times higher than that of 2-phenylpentane (Table IV) (14). The difference in C6-cyclization is even larger. Now, the side-chain carbon atoms involved in the cyclizations of n-butylbenzene and 2-phenylpentane have identical natures (i.e., secondary in five-membered ring closure and primary in six-membered ring closure). The difference between the two molecules (the extra methyl group) is far removed from the two carbon atoms involved in the formation of the new bond ... 

Consider an example using an ester. When an excess of ethylmagnesium bromide is added to methyl benzoate, the first equivalent adds and methoxide is expelled, giving propiophenone. Addition of a second equivalent, followed by protonation, gives a tertiary alcohol 3-phenylpentan-3-ol. 

Enantioselective Addition of Alkyllithium Reagents to Aldehydes. (25, 2 5)-2-Hydroxymethyl-l-[(l-methylpyr-rolidin-2-yl)methyl]pyrrolidine (1) is a chiral amino alcohol which binds well to alkyllithium reagents. Enantioselective addition of n-Butyllithium to benzaldehyde in the presence of (1) in a mixed solvent of Mc20 and dimethoxymethane (DMM) (1 1) at —123 °C affords (5)-l-phenylpentan-l-ol with 95% ee in 77% yield. In the addition to 3-methylbutanal, the corresponding (5)-alcohol is obtained in 80% ee (eq 1). 

Synonyms Benzyl isoamyl alcohol Benzyl isobutyl carbinol Isobutyl benzyl carbinol 4-Methyl-1-phenyl-2-pentanol 4-Methyl-1-phenylpentan-2-ol... 

Veticol acetate Vetikolacetate 3/080515. See 1,3-Dimethyl-3-phenylbutylacetate Vetikone 3/080505. See 4-Methyl-4-phenylpentan-2-one Vetival 3/980601. See 4-Cyclohexyl-4-methylpentan-2-one... 

Methyl phenylacetate Methylphenylbutanol 2-Methyl-4-phenyl-2-butyl isobutyrate 4-Methyl-4-phenylpentan-2-one Methyl 3-phenylpropionate... 

Methyl-4-phenylpentan-2-one Vetikone 3/080505 7414-83-7 Disodium etidronate Turpinal 2 NZ 7421-40-1... 

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