Abstract
Correction and Removal of Expression of Concern for ‘Highly stereoselective gram scale synthesis of all the four diastereoisomers of Boc-protected 4-methylproline carboxylates’ by Kehuan Sun et al., RSC Adv., 2019, 9, 32017–32020, DOI: https://doi.org/10.1039/C9RA06827A.
The authors regret that in the original ESI several impurity peaks were removed from the NMR spectra.
The authors have repeated their results and a new ESI file with new NMR spectra has been provided.
An independent expert has viewed the original and new spectra and has concluded that they are consistent with the discussions and conclusions presented.
This correction supersedes the information provided in the Expression of Concern related to this article.
The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.