80520-05-4Relevant academic research and scientific papers
Evolution of N-Heterocycle-Substituted Iodoarenes (NHIAs) to Efficient Organocatalysts in Iodine(I/III)-Mediated Oxidative Transformations
Boelke, Andreas,Nachtsheim, Boris J.
, p. 184 - 191 (2020)
The reactivity of ortho-functionalized N-heterocycle-substituted iodoarenes (NHIAs) as organocatalysts in iodine(I/III)-mediated oxidations was systematically investigated in the α-tosyloxylation of ketones as the model reaction. During a systematic catalyst evolution, it was found that NH-triazoles and benzoxazoles have the most significant positive influence on the reactivity of the central iodine atom. A further catalyst improvement which focused on the substitution pattern of the arene revealed a remarkable ortho-effect. By introduction of an o-OMe group we were able to generate a novel NHIA with a so far unseen catalytic efficiency. This new catalyst is not only easy to synthesize but also enabled the α-tosyloxylation of carbonyl compounds at the lowest reported catalyst loading of only 1 mol%. Finally, the performance of this iodine(I) catalyst was successfully demonstrated in intramolecular oxidative couplings of biphenyls and oxidative rearrangements. (Figure presented.).
Direct α-oxytosylation of carbonyl compounds: One-pot synthesis of heterocycles
John, Oliver R. S.,Killeen, Niall M.,Knowles, Deborah A.,Yau, Sze Chak,Bagley, Mark C.,Tomkinson, Nicholas C. O.
, p. 4009 - 4012 (2008/02/11)
N-Methyl-O-tosylhydroxylamine is an effective reagent for the direct α-oxytosylation of carbonyl compounds. The reactions proceed smoothly at room temperature in the presence of both moisture and air and functional group tolerance in the substrate is good. With nonsymmetrical substrates regioselectivity for primary over secondary centers is observed and complete regiospecificity for primary over tertiary centers is obtained. Addition of a bis-heteronucleophile directly to the crude reaction mixture in a one-pot process leads to the corresponding heterocyclic product.
