Diamagnetic-y-gauche effect

For more examples concerning various molecular systems in staggered conformations, the reader is referred to the compilations of diamagnetic y-gauche effects in refs. 7 and 9. The disappearance of a noticeable effect when the observed carbon atom is quaternary, that is, when no polarizable C-H bond is present, was also considered to support the above explanation (110,175). 

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