AI Article Synopsis
- The functionalization of alcohols in complex polyols is challenging, with progress made in selective oxygen derivatization but limited advancements in chemoselective oxidation to carbonyls.
- This research introduces a new reagent, nitrogen-ligated (bis)cationic λ-iodanes, which shows high selectivity for oxidizing equatorial alcohols while avoiding axial alcohols in cyclic systems.
- The methodology is mild and the reagent can be easily synthesized or generated in situ, making it a useful tool for chemists working on selective oxidation in various alcohol structures.
Article Abstract
The site-selective and chemoselective functionalization of alcohols in complex polyols remains a formidable synthetic challenge. Whereas significant advancements have been made in selective derivatization at the oxygen center, chemoselective oxidation to the corresponding carbonyls is less developed. In cyclic systems, whereas the selective oxidation of axial alcohols is well known, a complementary equatorial selective process has not yet been reported. Herein we report the utility of nitrogen-ligated (bis)cationic λ-iodanes (-HVIs) for alcohol oxidation and their unprecedented levels of selectivity for the oxidation of equatorial over axial alcohols. The conditions are mild, and the simple pyridine-ligated reagent () is readily synthesized from commercial PhI(OAc) and can be either isolated or generated in situ. Conformational selectivity is demonstrated in both flexible 1,2-substituted cyclohexanols and rigid polyol scaffolds, providing chemists with a novel tool for chemoselective oxidation.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7060929 | PMC |
| http://dx.doi.org/10.1021/acs.orglett.9b02018 | DOI Listing |
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