Oxiidizing Polymers: A Polymer-Supported, Recyclable Hypervalent Iodine(V) Reagent for the Efficient Conversion of Alcohols, Carbonyl Compounds, and UNsaturated Carbamates in Solution

摘要

Polymer-supported reagents and reactive intermediates can be applied successfully to the parallel conversion of single compounds as well as for the construction of chemical libraries by exploiting the advantages of solution-phase synthesis in combination with those of synthesis on a solid phase. The oxidation of alcohols to carbonyl compounds is one of the key transformations in organic synthesis because of the diversity of products that can be obtained from aldehyde and ketone precursors. Recently, polymer-supported oxoammonium salts were demonstrated to be reactive and versatile oxidation reagents. In contrast to previous methods, oxoammonium salts do not rely on heavy metal salts or on additional co-oxidants. The reactive intermediates derived from 4-alkoxy-2,2-6,6-tetramethylpiperidien-1-oxide (4-TEMPO) were used to oxidize a diverse collection of alcohols, mostly in excellent purity and yield. An extension to even more complex and sensitive substrates, preferably including those with nitrogen functionalities, would be highly desirable.