Thiele-Winter reaction

A more recent development in quinone chemistry has been the tandem reaction sequence. In seeking elegant syntheses of complex molecules, careful orchestration of transformations has become essential. The use of the Thiele-Winter reaction in tandem with arylation gives good yields of pharmacologically interesting heterocycles, such as (62), from 2,5-dihydroxy-l,4-ben2oquinone [615-94-1] and pyridines, where R = H or CH (60). 

Thiele-Winter Reaction (Acetoxylation) (Thiele Reaction)... 

The synthetic scope of the Thiele-Winter reaction of quinines with acetic anhydride can be increased by the use of triflic acid (eq 46). Reaction of cyclopropylacylsilanes with triflic acid in aprotic solvent affords the corresponding cyclobutanone or 2-silyl-4,5-dihydrofuran derivatives. Triflic acid can react with >-iodosylbenzoic acid to form a hypervalent iodine reagent, which reacts with 1-trimethylsilylalkynes to afford alkynyliodonium tri-flates bearing a carboxy group in high yields (eq 47). Reaction of (diacetoxyiodo)benzene [PhI(OAc)2] with excess triflic acid results in oligomerization of PhI(OAc)2- ... 

This reaction is related to Thiele-Winter Ac etoxylation. 

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