Bismuth triflate-catalyzed condensation of indoles with acetone

Abstract

Reaction of different substituted indoles with acetone was investigated using Bi(OTf) 3 as a catalyst. An efficient protocol was developed for the synthesis of spiro indoles, 1-methyl-cyclopenta[b]indole and bis(1-methyl-1H-indolyl)propanes via the reaction of indole with acetone in the presence of Bi(OTf) 3 .The reaction conditions were benign, required shorter reaction time, and gave good yields.

CF3SO2Na-Mediated, UV-Light-Induced Friedel–Crafts Alkylation of Indoles with Ketones/Aldehydes and Bioactivities of Products

“…Because of their biological potential, DIMs have received much attention in organic synthesis, and several highly efficient methods have been developed for their production. − One of them is the Cu-catalyzed cross-coupling of asymmetry substituted indole (Scheme a) . By means of organocatalysis, Huo et al developed a synthetic method to generate DIMs from sodium triphenylphosphine- m -sulfonate (TPPMS) and CBr 4 (Scheme b).…”

Synthesis of Bis(indolyl)methanes through an Alkylation Reaction of Indoles with Sodium Alkoxides

“…1, 126.3, 125.5, 121.3, 121.2, 120.5, 118.6, 111.0, 34.9, 29.9. The spectroscopic data matched those reported. 22…”

“…Unfortunately, the reaction needed to be conducted at 150 °C to maintain the reaction efficiency (entry 16). Finally, other H-acceptors instead of 1-tetralone were investigated; however, these reactions failed to provide higher yield (entries [17][18][19][20][21][22].…”

Orthometallated Pd(ii) C^N^S pincer complex catalyzed sustainable synthesis of bis(indolyl)methanesviaacceptorless dehydrogenative coupling of alcohols

“…[8][9][10] Traditional syntheses of BIMs rely heavily on the Friedel-Crafts alkylation reaction of indoles and carbonyl compounds catalysed by Lewis or Brønsted acids and transition metals. Even if some substrate-specific synthetic approaches exist, [11][12][13][14][15][16][17][18] they are undeterred due to the demand for high catalyst loadings, powerful oxidants, higher temperature, and relatively unstable aldehydes. In this context, recent interest has been piqued by the green and sustainable protocols, one of them is known as acceptorless dehydrogenative coupling (ADC) of alcohols, which can be considered as a productive tool for new C-X (X = C, O, N, S) bond formations in a highly atom economical and cost-effective way.…”