Substituent Effects on Carbon-13 Chemical Shifts in 2,6-Disubstituted Adamantanes

Article abstract of DOI:10.1002/mrc.1270170305

Carbon-13 NMR spectral data for a series of symmetrical 2,6-disubstituted adamantanes (O=, CH2=, CH3, OH, OCOCH3) are presented.The substituent effects on 13C chemical shifts are additive, except for carbons 2 and 6 in 2,6-adamantanedione.The non-additivity of the substituent effect in the diketone can be interpreted in terms of a through-space interaction of the carbonyl ?-electrons; the additivity in the other derivatives indicates that there is no appricable interaction between the substituents.