An easy way for constructing hard-to-make epoxides employing HOF·CH3CN

Elemental Fluorine and HOF·CH3CN in Service of General Organic Chemistry

“…methyl 4-nitrophenyl sulfide (32), aliphatic sulfides -even the sterically hindered ones like di-tert-butyl sulfide (33), were all oxidized to the corresponding sulfones in quantitative yield in 4-6 minutes. The reaction proceeds well also when two sulfur atoms were present in the same molecule as in 2-methyl-1,3-dithiane (34). The corresponding disulfones were obtained at room temperature in a few minutes and in higher than 90 % yield (Scheme 10).…”

“…[34] Tropone (6) has never been directly epoxidized. [34] Tropone (6) has never been directly epoxidized.…”

“…[45] In addition, the reactions may require many hours and high temperatures. The reaction proceeds well also when two sulfur atoms were present in the same molecule as in 2-methyl-1,3-dithiane (34). [46] Sulfides with electron-donating aromatic rings such as methyl p-tolyl sulfide (31), electron-withdrawing ones, e.g.…”

“…To conclude this subject, it would be illuminating to compare a few epoxidation methods of some unique olefins with respect to reaction yields, conditions and times. [34] Tropone (6) has never been directly epoxidized. The only method reported for the preparation of its triepoxide involved five steps, which took 4 days and consecutive use of a number of oxidizing agents.…”

New Conjugated Oligothiophenes Containing the Unique Arrangement of Internal Adjacent [All]‐S,S‐Oxygenated Thiophene Fragments

“…It was instrumental in quite a few difficult oxygentransfer reactions, such as in the oxygenation of either electron-depleted or sensitive sulfur-containing compounds, [10] in the preparation of linear [11] and star-shaped [12] [all]-S,S-oxygenated oligothiophenes, in oxidizing thienopyrroles, [13] and more. [14] Other previously unknown or very difficult reactions involved the transfer of oxygen atoms to nitrogen atoms forming various N À O derivatives, [15] reactions resulting in "impossible" epoxidations, [16] tertiary hydroxylations, [17] forming azulene derivatives, [18] and more, have also been described. [19] In her highly interesting chapter in the Handbook of Thiophene-Based Materials, [20] Barbarella described some partially oxygenated oligothiophenes and stated that two or three adjacent central S,S-oxygenated thiophene rings incorporated into a conjugated chain should have a much greater effect on the electron affinity than that achieved up to that time by any other combination of S,S-oxygenated and nonoxygenated thiophenes.…”