Zinc‐Catalyzed Direct Cyanation of Indoles and Pyrroles: Nitromethane as a Source of a Cyano Group

Abstract

With nitromethane and diphenylsilane (Ph 2 SiH 2 ), zinc triflate behaves as a Lewis acid catalyst for the cyanation of nitrogen-containing heteroarenes such as indoles and pyrroles. This is the first realization of the Lewis acid-catalyzed direct cyanation of a CA C H T U N G T R E N N U N G (aryl) À H bond with no CN group-containing cyanating agent.

Easy Access to a Library of Alkylindoles: Reductive Alkylation of Indoles with Carbonyl Compounds and Hydrosilanes under Indium Catalysis

“…Under an argon atmosphere, potassium hydroxide (449 mg, 8.00 mmol) and dimethyl sulfoxide (5.0 mL) were placed in a flame‐dried 20‐mL Schlenk tube, and stirred at room temperature for 10 min. To the tube was added 5‐methyl‐3‐propyl‐1 H ‐indole26 (347 mg, 2.00 mmol), and then iodomethane (284 mg, 2.00 mmol) was slowly added dropwise with stirring. After stirring at room temperature for 45 min, the reaction mixture was filtered to remove an excess amount of potassium hydroxide, and the filtrate was diluted with Et 2 O (100 mL).…”

Synthesis Strategies for α‐, β‐, γ‐ and δ‐Carbolines

“…According to the difference of cyclized rings, the synthesis of δ‐carboline can be divided into four types, including constructing pyrrole ring via transition metal‐catalyzed coupling reaction or photocyclization of anilinopyridines, [16a,68] cyclization of pyridine and benzene rings through the Grignard [69] and Heck reactions, [70] respectively. Meanwhile, [2+2+2] cycloaddition and the Domino reaction are also use to construct δ‐carbolines [29,71] …”

Benzannulation of Pyrroles to 4,5‐Disubstituted Indoles through Brønsted‐Acid‐Promoted Rearrangement of tert‐Butyl Peroxides

“…Compounds 11 were prepared according to our previous work . Pyrroles 12 b – g , 12 h and 12 i , 12 j , 12 k , and 12 l were prepared according to literature reports.…”