J. Org. Chem., 68, 2506 (2003)

Compound #7 of this paper has a -CH - ( CH2 - I ) - moiety, the CH2-group attached to the iodine atom is given at 75.3 ppm.


Iodine is known to induce a strong highfield-shift, therefore a value of 75.3ppm is easily identified as an extreme outlyer. Recalculation of the spectrum gives 12.8ppm (CSEARCH-HOSE; range 10.5 - 15.9ppm) and 13.8ppm (CSEARCH-NN). Obviously there is a difference of approximately 60ppm between the literature value and both predicted values - this makes this example interesting for further analysis.

In the 'Supplementary Information' the C-NMR spectrum of compound #7 can be found on page 'S15'. There is the severly overcrowded region between 70 and 80ppm, where nearly all CH-O and CH2-O are located. In the high-field region there is a single signal at 16ppm clearly visible, which can be easily attributed to the -CH2-I group.

Therefore the summary is:


This article shows, that we have clearly to distinguish between the 'LITERATURE VALUE' for the chemical shift of a certain carbon and the 'EXPERIMENTAL VALUE', which has been really measured !

In the case of applying a 'robot-referee' during the peer-reviewing process to this set of C-NMR data, it would be impossible to ignore this error.

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Page written on:  March 6th, 2008
Page online since:  March 6th, 2008