Cross dehydrogenative coupling of N-aryltetrahydroisoquinolines (sp³ C–H) with indoles (sp² C–H) using a heterogeneous mesoporous manganese oxide catalyst

Abstract

We disclose a novel, heterogeneous catalytic approach for selective coupling of C1 of N-aryltetrahydroisoquinolines with C3 of indoles in the presence of mesoporous manganese oxides.

Oxidative Dearomative Cross-Dehydrogenative Coupling of Indoles with Diverse C-H Nucleophiles: Efficient Approach to 2,2-Disubstituted Indolin-3-ones

“…Over the past decades, oxidative CDC reactions have gained tremendous attention since the pioneering work of Li, and numerous oxidative systems have been successfully developed [13][14][15][16][17][18]. Under the developed oxidative conditions, indoles have been widely used as nucleophiles in a number of CDC reactions owing to the strong nucleophilicity of indole rings [19][20][21][22][23][24][25][26][27][28][29]. In contrast, reactions of indoles with other nucleophiles have not been well investigated [30][31][32][33][34][35].…”

Aerobic Self‐Esterification of Alcohols Assisted by Mesoporous Manganese and Cobalt Oxide

“…For meso MnOx the active phase is believed to be Mn 2 O 3 due to the presence of Mn 3+ . Mechanistic studies on meso MnOx suggest a redox reaction between Mn 3+ and Mn 2+ is essential for catalysis . Meso MnOx calcined at 350 °C is shown to be mainly amorphous while at 450 °C shows a clear presence of Mn 3 O 4 and Mn 2 O 3 .…”

Aerobic Oxidative Functionalization of Indoles

“…Later in 2017, Suib group developed the same CDC reaction using a heterogeneous mesoporous manganese oxide catalyst, again under aerobic conditions (Scheme 20, conditions E). [54] Moderate to excellent yields were generally afforded. The authors also carried out a detailed mechanistic investigation of the reaction on the catalyst surface, backed by DFT computational studies, which thereby help to understand the superior catalytic activity of manganese oxides.…”