Nmr analysis of α-methyl branched organic acids

✍ Scribed by William L. Senn Jr.; Lloyd A. Pine

• Book ID: 104102590
• Publisher: Elsevier Science
• Year: 1964
• Tongue: English
• Weight: 398 KB
• Volume: 31
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/s0003-2670(00)88853-4

✦ Synopsis

During a study of KOCH'S~ carboxylic acid synthesis, it became necessary to develop a quick, simple method of analyzing for the diffcrcnt types of isomers produced. In this synthesis, an olefin is reacted with carbon monoxide in the presence of a strong acid catalyst to produce a catalyst-olefincarbon monoxide cornp1ex. Subsequent hydrolysis of this complex produces a carboxylic acid.

As a result of this carbonium ion mechanism, the product contains all of the structures shown below. (R = alkyl group larger than methyl.)

In order to dctcrminc the cffcct of reaction conditions on the rclativc amounts of these isomers in the product, the following technique of analysis by NMR was dovclopcd.