According to the notices, after the editors of Organic & Biomolecular Chemistry confirmed the problems, they contacted the corresponding author on the three papers, Pradeep Kumar—who works at the Council of Scientific and Industrial Research (CSIR)-National Chemical Laboratory in Pune, India—as well as the director of CSIR, Ashwini Kumar Nangia. The institution conducted its own internal review of the spectra and concluded the authors did not intentionally alter them.
Still, the journal and institution could not confirm the accuracy of the data, and the journal published expressions of concern to warn readers about the issues.
It has been brought to the Executive Editor’s attention that there are a number of unexplained discrepancies (visible under magnification) in the NMR spectra presented in the ESI accompanying this article. These have been confirmed by independent review by a member of the Editorial Board.
The affected spectra are: 13C NMR spectra for; 16, 19, 20, 26, 39, 34, 35, 36 and 12; 1 H NMR spectra for; 26, 34, 35, 36 and 12.
Following consultation with the authors and the Director of CSIR-National Chemical Laboratory, we have established that archive copies of the original data supporting these spectra are no longer available for comparison. After carrying out an internal review the Director of CSIR-National Chemical Laboratory has determined that there was no intentional altering of the published NMR spectra.
However as the accuracy of these NMR spectra cannot be confirmed the Executive Editor is issuing this notice for readers’ information.
The 2010 paper has been cited 26 times, according to Clarivate Analytics’ Web of Science.
The language in the other two expressions of concern is identical, though both notices call out different spectra. The expression of concern for “Organocatalytic stereoselective synthesis of passifloricin A” highlights the affected spectra:
13C NMR for; 10, 11, 19, 20, 21 and 22, 1H NMR for; 13, 19, 20, 21, 22 and 1.
The 2012 paper has been cited 18 times.
The expression of concern for “Enantio- and diastereocontrolled conversion of chiral epoxides to trans-cyclopropane carboxylates: application to the synthesis of cascarillic acid, grenadamide and L-(-)-CCG-II” highlights the affected spectra:
13C NMR spectra for; 11, 13, 17, 20, 15 and 21, 1H NMR spectra for; 17 and 21.
The 2012 paper has been cited nine times.
The nature of the errors isn’t entirely clear, nor why so many spectra were affected.
Richard Kelly, the executive editor at the Royal Society of Chemistry, which publishes the journal, told us:
These were not picked up during peer review as they were only evident under high magnification.
We contacted Kumar as well as Nangia for more information, but neither responded.
Earlier this year, we reported that the same journal had decided to swap a 2015 expression of concern with a correction notice, after the authors addressed the editors’ concerns in a follow-up paper.
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