CONFIGURATIONS AND PMR SPECTRA OF IODI LACTONES AND OXYMERCURIALS DERIVED FROM SOME 5-NORBORNENE-2-ENDO-CARBOXYLIC ACIDS

Iodo lactones and chloromercuri lactones derived from a number of 2- and 3-methyl-5-norbornene-2-endo-carboxylic acids have been prepared and characterized. Analyses of 60-MHz and 100-MHz proton magnetic resonance spectra have established their configurations, which conform to a general pattern of trans-addition. Criteria for stereochemical assignments in this system can be based upon identifiable vicinal, geminal, and some long-range 1H–1H and 1H–199Hg coupling constants. These criteria are used to establish that 5-norbornene-2-endo,3-endo-dicarboxylic acid and its derivatives do not follow the cis-oxymercuration route previously suggested. © 1969, CSIRO. All rights reserved.