4-Methylpentanoic Acid

We see that a secondary alkyl halide is needed as the alkylating agent The anion of diethyl malonate is a weaker base than ethoxide ion and reacts with secondary alkyl halides by substitution rather than elimination Thus the synthesis of 3 methylpentanoic acid begins with the alkylation of the anion of diethyl mal onate by 2 bromobutane... 

As actually carried out and reported in the chemical literature diethyl malonate has been alkylated with 2 bromobutane in 83-84% yield and the product of that reaction converted to 3 methylpentanoic acid by saponification acidification and decarboxylatlon in 62-65% yield j... 

Methyl malonatc, 13, 100 Methyl 0-naphthyl ketone, 17, 65 Methyl nitrite, 16, 44 Methyl oxalate, 10, 70 3-Methylpentanoic acid, 11, 76 Methyl 0-phenylethyl ketone, 16, 49... 

N,N,o-trimethyl-, 34, 61 N-Benzylaniline, 36, 22 Benzyl chloride, 34, 65 Benzyl cyanide, 31, 53 32, 64, 65, 92 N-Benzylidenemethylamine, 34, 65 Benzyl isocyanide, 31, 54 Benzylmagnesium chloride, 34, 65 3-Benzyl-3-methylpentanenitkile, 35, 8 3-BENZYL-3-METHYLPENTANOIC ACID, 35, 6 /S-Benzyl-/ -methylvaleric acid, 35, 6 Benzylthiosulfuric acid, 32, 103 Benzyltrimethylammonium hydroxide,... 

Amino-a-methylbenzyl alcohol, a256 2-Amino-3-methylpentanoic acid, i88 2-Amino-2-methylpropane, b511... 

Isoleucine (He or I) ((25,35)-2-amino-3-methylpentanoic acid) is a nonpolar, neutral, aliphatic amino acid with the formula HOOCCH(NH2)CH(CH3)CH2CH3. Having a hydrocarbon side chain. He is classified as a hydrophobic amino acid. Together with Thr, He is one of the two common amino acids that have a chiral center. Although four stereoisomers of He are possible. He present in nature exists in only one enantiomeric form, that is, (25,35)-2-amino-3-methylpentanoic acid. ... 

If a brownish color or a wide range of the boiling point of the main fraction is observed, redistillation is recommended. Redistillation is necessary for (2S,3S)-2-chloro-3-methylpentanoic acid. Yields are given in Table. Enantiomeric purities (see Table) were determined after conversion to tert-butyl amides (catalyzed by dicyclohexylcarbodilmide, 30 min at 0°C in... 

The aliphatic acids isolated from a California crude petroleum by Lochte and coworkers (31) include 2-methylpentanoic acid, 3-methylpentanoic acid, n-hexanoic acid, 2-methylhexanoic acid, 3-methylhexanoic acid, 4-methylhexanoic acid, 5-methylhexanoic acid, n-heptanoic acid, n-octanoic acid, and n-nonanoic acid. 

In diene hydroformylation with complex (34) and DIOP, the attainable optical yields were critically dependent on the diene. Thus isoprene gave, after oxidation of the aldehyde with Ag20, 3-methylpentanoic acid as major product having an optical purity of 32%. Butadiene, 2,3-dimethylbutadiene and 2-methyl-1-butene all gave optical yields of less than 6%. 369 The hydroformylation by (34) and DIOP of a number of alkenes having C2v symmetry gave best results with m-2-butene, with an optical yield of 27%.370... 

BENZYL-3-METHYLPENTANOIC ACID (p-Benzyl-p-methylvaleric acid)... 

D. 3-Benzyl-3-methylpentanoic acid. A solution of 112 g. of potassium hydroxide in 400 ml. of ethylene glycol is added to 93.6 g. (0.5 mole) of 3-benzyl-3-methylpentanenitrile in a 1-1. round-bottomed copper or stainless-steel flask. A condenser with a rubber stopper is attached, and the solution is heated under brisk reflux for 6 hours (Note 12). The reaction mixture is cooled, diluted with 400 ml. of water, and extracted with three portions of ether (250 ml., 100 ml., 100 ml.). The ether... 

When the combined aqueous washes from three runs were acidified, extracted, and distilled, there was obtained 1.8 g. of 3-benzyl-3-methylpentanoic acid, 1.5158. 

The ethyl 3-benzyl-2-cyano-3-methylpentanoate, 3-benzyl-3-methylpentanenitrile, and 3-benzyl-3-methylpentanoic acid preparations follow the procedure given by Prout, Huang, Hartman, and Korpics.9... 

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