Synthesis of Diverse Phenothiazines by Direct Thioamination of Arynes with S-(o-Bromoaryl)-S-methylsulfilimines and Subsequent Intramolecular Buchwald–Hartwig Amination

Reactions of Sulfoxides with Benzynes

“…Interestingly, Yoshida, Hosoya, and co-workers found that the intramolecular aryl-migration products 12 could be obtained efficiently at a high temperature (80 or 110 °C) in 1,4-dioxane (Scheme 6b ). 13 It is worth mentioning that a similar transformation of sulfilimines had been previously reported by the same group in 2015. 14…”

o-Silylaryl Triflates: A Journey of Kobayashi Aryne Precursors

“…In this study, they also found that when sulfilimine contains a methyl group, o -arylthio aniline could be obtained. This transformation was then applied in the preparation of diaryl sulfides 7-140 by using S -( o -bromoaryl)- S -methylsulfilimines 7-139 as the substrates (Scheme b) . A subsequent intramolecular Buchwald–Hartwig amination operation was able to convert 7-140 to phenothiazine.…”

“… Among those products, 6,7-bis­[(pinacolato)­boryl]­indole 12-67 could undergo C7-selective Suzuki–Miyaura cross coupling reactions to afford 12-70 . Moreover, Kobayashi precursors of indolynes have been extensively utilized as hetaryne substrates along with benzyne transformations. ,,,,,,,,,,,,,,,, …”

“…This transformation was then applied in the preparation of diaryl sulfides 7-140 by using S-(o-bromoaryl)-S-methylsulfilimines 7-139 as the substrates (Scheme 118b). 550 A subsequent intramolecular Buchwald− Hartwig amination operation was able to convert 7-140 to phenothiazine. Moreover, they disclosed that the SN bond of sulfoximines 7-141 could be inserted by arynes (Scheme 118c).…”

Synthesis of Diverse γ-Aryl-β-ketoesters via Aryne Intermediates Generated by C–C Bond Cleavage

“…1 In particular, γ-aryl-β-ketoesters have been used as key intermediates in the synthesis of naturally occurring products and pharmaceuticals via diverse transformations, including ring closure reactions to construct a fused six-membered ring (Figure 1). 2,3 Despite the usefulness of γ-aryl-β-ketoesters, most of their synthesis have been achieved by conventional methods, such as the Knoevenagel condensation of Meldrum's acid followed by pyrolysis 4 or palladium-catalyzed arylation of disilyl dienolates. 5 Herein, we report an alternative method for the synthesis of diverse γ-arylβ-ketoesters via aryne intermediates, which are generated via C−C bond cleavage of 6-(triflyloxy)benzocyclobutenols.…”