110-43-0 2-Heptanone

Submitted by Robert Davis, Charles Granito, and Harry P. Schultz 1 

A mixture of 370 ml. (4 moles) of zt-butyric acid (Note 1) and 123 g. (2.2 moles) of hydrogen-reduced iron powder (Note 2) is refluxed for 5 hours in a 1-1. flask equipped with a condenser (Note 3). The apparatus is converted for downward distillation while an atmosphere of nitrogen is maintained. The nitrogen sweep is then stopped, the flask is strongly heated, and the entire distillate collected. 

The crude product is washed with two 20-ml. portions of 10% sodium hydroxide solution and with one 20-ml. portion of water. The 4-heptanone is dried over 5 g. of anhydrous sodium sulfate, filtered, and distilled. The yield of 4-heptanone, b.p. 142-144°, n25D 1.4031 -1.4036, is 157-171 g. (69-75%). 

w-Butyric acid, b.p. 162-364°, from Eastman Organic Chemicals was redistilled before use. 

Hydrogen-reduced iron powder from Fisher Scientific Company was used. 

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The ketone 2 heptanone has been identified as contnbuting to the odor of a number of dairy products including condensed milk and cheddar cheese Describe a synthesis of 2 heptanone from acetylene and any necessary organic or inorganic reagents... 

Methyl Amyl Ketone. Methyl amyl ketone [110-43-0] (MAK) (2-heptanone) is a colorless Hquid with a faint fmity (banana) odor. It is found in oil of cloves and cinnamon-bark oil, and is manufactured by the condensation of acetone and butyraldehyde (158). Other preparations are known (159-162). 

Methyl(/i-amyl)ketone (2-heptanone) 5-Methyl-3-heptanone Methyl acetate Methyl acetylene... 

This reaction sequence is called the acetoacetic ester synthesis. It is a standard procedure for the preparation of ketones from alkyl halides, as the conversion of 1-bromobutane to 2-heptanone illustrates. 

The ant Iridomyrmex pruinosus utilizes 2-heptanone as an alarm pheromone. Figure 17 illustrates the existence of a close correlation of the similarity between 2-heptanone and its analogs in molecular model silhouettes with their alarm activity45. It is noteworthy that the replacement of the methylene group in position 3 of 2-heptanone by the ether linkage yields n-butyl acetate which has the same activity as the natural pheromone. Considerable activity is still retained even when the carbonyl group is replaced by the hydroxyl group. 

Fig. 17. Correlation of the molecular silhouettes of the natural alarm pheromone (2-heptanone) and its analogs with their alarm activity45 (Copyright 1969 by the AAAS)...

Heptane, 1 eromo 2 fluoro, 46,10 Heptanoic acid, 2 fluoro, 46,37 2 Heptanone, 47, 89 4-Heptanone, 47, 7S Heptanoyl fluoride, 46, 6... 

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