Triphenylcarbenium Tetrafluoroborate‐Catalyzed 1,6‐Addition of 1‐Aminobenzotriazole to p‐Quinone Methides: Synthesis of Diarylmethylamines

Abstract

A metal‐free synthesis of diarylmethylamines via triphenylcarbenium tetrafluoroborate‐catalyzed 1,6‐addition of 1‐aminobenzotriazole to p‐quinone methides (p‐QMs) was developped. Under mild condition, diarylmethylamines could be obtained in moderate to good yields (up to 84%) by simple filtration, showing essentially unchanged activity after 6 reuses.

Application of Triaryl Carbenium in Organic Synthesis

“…catalyzed bromination of arenes [14] Roskamp 反应中同样表现出良好的催化性能, 均以较好 的收率得到 α-支链 β-酮羰基化合物(Scheme 5a). 2022 年, 他们 [16] 以[Tr] ＋ [BF 4 ] -作为催化剂, 实现了 1-氨基苯 并三唑与对亚甲基苯醌(p-QMs)之间的 1,6-加成反应, 得到一系列二芳基甲胺类化合物(Scheme 5b).…”

“…-催化 1,2-氢迁移和 1,6-加成反应 [15][16] Scheme 5 [Tr] ＋ [BF4] --catalyzed 1,2-hydride migration and 1,6-addition reactions [15][16] 图式 6 [Tr] ＋ [BF4]…”

A Ritter‐Type Route to Diarylmethane Amides from para‐Quinone Methides

“…In this context, the p-QMs are utilized in 1,6-conjugate addition/aromatization reactions as Michael acceptors to construct carbon À carbon and carbon À heteroatom bonds in the presence of different catalysts and bases, and deliver core structures of numerous natural and synthetic molecules. [19][20][21] In the case of nitrogen-centered nucleophiles, p-toluenesulfonic acid (PTSA)-catalyzed addition of anilines, [22] PTSA-catalyzed addition of NH-sulfoximines, [23] HFIP-catalyzed addition of indolines, [24] triphenylcarbenium tetrafluoroborate (Ph 3 CBF 4 )catalyzed addition of 1-aminobenzotriazoles, [25] and both recyclable bismuth complex-catalyzed [26] and Zn(OTf) 2 -promoted [27] reactions of N-heterocycles with p-QMs were reported. However, the 1,6-addition of nitriles as nitrogen-nucleophile to p-QMs has not been investigated to date.…”