Anticancer-active 3,4-diarylthiolated maleimides synthesis via three-component radical diarylthiolation

Abstract

Herein, we report an efficient and simple copper-catalyzed oxidative diarylthiolation of maleimides with sulfur powder and aryl boronic acids, in which S powder was used as a substrate and internal oxidant. The corresponding double C-S bonds coupling products were obtained in moderate to high yields under a simple catalytic system. Mechanistic studies indicated that copper-catalyzed radical thiolation of aryl boronic acids with S powder, and the resulting arylthiyl underwent radical addition with double bonds of maleimides.

Recent advances in selective mono-/dichalcogenation and exclusive dichalcogenation of C(sp2)–H and C(sp3)–H bonds

“…In the same year, Alves and coworkers described a CuI-catalyzed ultrasonic-promoted three-component synthesis of mono-or diselenylated pyrroles 69-70 from primary amines 67, 2,5-hexanedione 68 and diorganyl diselenides 39 via suc- In the same year, Yu and coworkers accomplished a threecomponent synthesis of 3,4-diarylthiolated maleimides 75 via CuI/X-Phos-catalyzed oxidative radical diarylthiolation of maleimides 71 with sulfur powder and aryl boronic acids 74, using sulfur power as both the sulfur source and an internal oxidant under oxygen atmosphere (Scheme 18). 150 The reaction exhibited high chemoselectivity and no monoarylthiolated or S-Michael addition by-products were observed. As depicted in Scheme 18, the disproportionation of sulfur powder provides sulfide anion (S 2− ) and high-valent sulfate (SO 3…”

Recent advances in the dichalcogenation reactions of unsaturated compounds via double functionalization

“…Three years later, Yu and coworkers accomplished a three-component synthesis of 3,4-diarylthiolated maleimides 14c via CuI/XPhos-catalyzed oxidative radical diarylthiolation of maleimides 14a with sulfur powder and aryl boronic acids 14b , using sulfur powder as both the sulfur source and an internal oxidant under an oxygen atmosphere (Scheme 14). 29 The reaction exhibited high chemoselectivity, and no mono-arylthiolated or S -Michael addition by-products were detected. The protocol was tolerant of a wide range of aryl boronic acids and maleimides, and was particularly suitable for the reaction of sterically hindered mesityl boronic acid and the two-fold reactions of bis-maleimide substrates.…”