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Substituent effects are widely used to investigate the factors affecting carbon‐13 chemical shifts. Adamantane and its derivatives are convenient probes for relative contributions to these factors owing to their symmetry and relative absence of ring strain. We have extended our studies on NMR chemical shifts of 1‐ and 2‐methyladamantanes to hydroxy, bromo, methoxy and acetamide substituents and also certain disubstituted (one of the groups being methyl) analogs. DFT/GIAO calculations at the B3LYP/6–31G(d,p) level show that, except for α‐effects, steric interactions are mainly responsible for substituent effects on chemical shifts. The CHARGE program is particularly well suited for localizing these effects and estimating their approximate shape and range.

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"C NMR spectra of 36 endo-endo, exo-enúo and ex-xo tetracyclic fused norbornyl compounds are interpreted.Stereochemical influences on 'H and "C chemical shifts are compared and discussed. Only upfield S and E effects are observed.