Complete regioselective formation of 2‐(arylsulfinyl)diphenyl sulfides from 5‐arylthianthreniumyl perchlorates

Abstract

Treatment of 5‐arylthianthreniurnyl perchlorates with potassium tert‐butoxide in dimethyl sulfoxide at room temperature gave 2‐(arylsulfinyl)diphenyl sulfides (29–79% yields), which are the first examples for complete regioselective formation of S‐monoxides from unsymmetrical arylthiodiphenyl sulfides.

Hydroxylation of Aryl Sulfonium Salts for Phenol Synthesis under Mild Reaction Conditions

“…In addition to the classic methods developed in order to access phenols by virtue of Sandmeyer reactions and direct arene oxidation [ 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ], the transition-metal-catalyzed hydroxylation of aryl halides has also been proven to be one of the most efficient methods by which to synthesize phenol [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. A range of hydroxide sources and their surrogates, such as alkali metal hydroxide (MOH) [ 18 , 19 , 20 , 21 ], water [ 22 , 23 , 24 , 25 , 26 , 27 ], boric acid [ 28 ], molecular oxygen [ 29 , 30 ], silanol [ 31 ], hydrogen peroxide [ 31 ], and nitrous oxide [ 32 , 33 ], have been revealed to be effective for the hydroxylation of aryl halides and its variants ( Scheme 1 a). In 2016 and 2017, the group of Fier and Maloney originally disclosed that benzaldoxime [ 34 , 35 , 36 , 37 ] and acetohydroxamic acid [ 38 ] could also function as effective hydroxylating agents for the conversion of aryl halides to phenols ( Scheme 1 b).…”

“… Hydroxylation of aryl halides and their counterparts. ( a ) Hydroxylation of aryl halides by using various hydroxide sources [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]; ( b ) Hydroxylation of aryl halides by using oxime and acetohydroxamic acid [ 34 , 35 , 36 , 37 , 38 , 39 ]; ( c ) Hydroxylation of other aryl electrophiles by using oxime and hydroxamic acid [ 48 , 49 , 50 ]; ( d ) Hydroxylation of aryl sulfonium salts by using oxime and hydroxamic acid (this work). …”