Cascade trifluoromethylthiolation and cyclization of N-[(3-aryl)propioloyl]indoles

Abstract

A cascade oxidative trifluoromethylthiolation and cyclization of N- [(3-aryl)propioloyl]indoles with AgSCF 3 is described. This protocol allows for the synthesis of novel bis(trifluoromethylthiolated) or trifluoromethylthiolated pyrrolo[1,2-a]indol-3-ones in moderate to good yields. Mechanistic investigations indicated that radical processes were probably involved in these transformations. 657

A General and Highly Versatile Heterogeneous Pd‐Catalyzed Oxidative Aminocarbonylation of Alkynes with Aromatic and Aliphatic Amines

“…At this point, an optimization of the reaction parameters employing [Pd/Mg 3 Al-LDH]-500 as catalyst was performed (Table 1, entries [9][10][11][12][13][14][15][16][17][18][19][20][21][22]. In first place, the amount of TBAI was studied (Table 1, entries 6 and 9-11) determining that the reaction undergoes with an optimum yield when this additive is employed at 5 mol % and, in its absence, diphenylbutadiyne was the only reaction product detected (Table 1, entry 9).…”

“…(%) [b] 3 (%) [b] 100 °C and employing a 2.5 mol % of Pd (Table 1, entry 6 and entries [16][17][18][19]. Several solvents were also evaluated (Table S1, SI), confirming ethyl acetate as the best one.…”

“…In addition, this class of compounds are highly versatile intermediates in the synthesis of heterocycles bearing a lactam or cyclic carbamate moiety in their structure (Scheme 1, A). In fact, butyrolactams, [12] spirolactams, [13][14] benzapines, [15] oxazolidinones, [16] quinolinones, [13] oxindoles [17][18] and pyrroloindolones [19] have been accessed from the corresponding alkynamides. Considering the great potential of heterocycles as biological active compounds, the cyclization of propiolamides is an interesting approach that has been already applied for accessing to relevant compounds.…”

An aerobic copper-mediated domino process for the synthesis of 3-(trifluoromethylseleno)indoles

“…11–14 Taking cues from the positive effect of fluorinated substituents, it was envisioned that introducing fluorine-containing groups on the indole rings could increase their bioactivity. In this context, a flourish of activity in the development of synthetic approaches to fluorinated, 15 trifluoromethylated 16–22 or trifluoromethylthiolated 23–37 indoles has recently been witnessed in the literature. Despite these great significances, the synthesis of trifluoromethylselenolated indoles is rarely explored and is mainly relied on strategies employing electrophilic or radical trifluoromethylselenolation of existing indole cores.…”

Copper- and Visible-Light-Catalyzed Cascade Radical Cyclization of N-Propargylindoles with Cyclic Ethers

“…In recent years, radical cyclization has been found to be an important method for the synthesis of pyrrolo­[1,2- a ]­indole derivatives. , Using arylsulfonyl hydrazides and arylthiophenols as free radicals precursors, the methods for the synthesis of 2-arylthiolated pyrrolo­[1,2- a ]­indoles have been developed (Scheme a). 2-Phosphoryl-pyrrolo­[1,2- a ]­indoles were prepared through tandem cyclization of N -propargylindole and P­(O)-H derivatives with transitional metals copper or silver salts as a catalyst (Scheme b). , In 2020, Tang and colleagues established a visible-light-mediated, iridium-catalyzed radical cyclization of N -propargylindole with acid chloride to prepare 2-acyl-9 H -pyrrolo­[1,2- a ]­indoles.…”