Mechanism of stereospecific alcohol elimination from cyclohexane trans-1,3-dicarboxylates under electron impact ionization

✍ Scribed by A. Etinger; A. Idina; A. Mandelbaum

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 373 KB
• Volume: 29
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/oms.1210290703

✦ Synopsis

Diesters of cyclohexaae trPns-l,3dicarboxylc acid give rise to major [ M -ROH] +' ions under electron impact ionization. A mass spectral study of the isomeric mixed methyl ethyl esters of the diacid, substituted by a methyl group at position 1 and deuterium labelled at position 3, indicates a stepwise mechanism for this alcohol elimination; the $hydrogen (or deuterium) is transferred to the carbonyl of the lester group in the initial step. Subsequent migration of that hydrogen (or deuterium) to the alkoxyl of position 3 results in the highly site-and stereospecific alcohol elimination. CID spectra of the [ M -ROH] + * ions obtained from the stereoisomeric diesters clearly show that they have different structures (or are different mixtures of structures).