4.5- Dimethylhexanoic acid

The malonic ester synthesis cannot be used to make 2,2-dimethylhexanoic acid. Explain why not. 

Regioselective arylation of substituted isoquinolines was also viable. Notably, by switching Irom pivalic acid to 2,2-dimethylhexanoic acid, less reactive pyridine substrates, such... 

Isobutyric acid added to Li-diisopropylamide prepared from n-butyllithium and diisopropylamine at 0° in tetrahydrofuran-heptane (or hexane), then allowed to react with n-butyl iodide 2,2-dimethylhexanoic acid. Y 89%. - Similarly with 17y, 20-epoxy-17a-methyl-5-androsten-3y -ol at 40° spirolactone. Y 81%. F. e. s. P. L. Greger, Am. Soc. 89, 2500 (1967). ... 

The longest chain has six carbons, and the carboxyl carbon is automatically assigned the number 1. The parent compound is therefore hexanoic acid. The substituents are listed numerically to give the correct name of the compound 3-chloro-4,5-dimethylhexanoic acid. 

Number the chain to put COOH at Cl. 6 carbon chain = hexanoic acid 3,3-dimethylhexanoic acid... 

The longest chain here is fairly obvious and has six carbon atoms, so this is a hexanoic acid. Add the substituents, thus 3,4-dimethylhexanoic acid. The commonest error in problems of this type is not to start the numbering scheme on the carboxylic acid carbon atom. Despite the presence of a ketone, this will be named as a carboxylic acid, so the chain is numbered from the -COOH group. 

Hexanoic acid, 4,6,6,6-tetrachloro-3,3-dimethyl-, methyl ester. EINECS 265-005-4 Hexanoic acid, 3,3-dimethyl-4,6,6,6-tetrachloro, methyl esten Hexanoic acid, 4,6,6,6-tetrachloro-3,3-dimethyl-, methyl ester Methyl 4,6,6,6-tetrachloro-3,3-dimethylhexanoate ... 

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