Synthesis of azafluorenones and related compounds using deprotocupration–aroylation followed by intramolecular direct arylation

Synthesis of Heteroarene‐Fused Cyclopentadienes and Related Compounds Suitable for Metallocene Preparation

“…[82] Halo-substituted 4-azafluorenes 8 and 9 were obtained in low yields from the corresponding 5-haloindanones. [83] Azafluorenones 10-13 were obtained via the Pdcatalyzed cyclization of (2-chloropyridin-3-yl)aryl ketones and (2-chlorophenyl)pyridyl ketones, [84,85] or (bromopyridyl)(bromophenyl)methanol. [86] These compounds were brominated at the benzene ring to form mono-and dibromo derivatives 14 and 15 (Scheme 4).…”

“…[97] Rhodium(III)-catalyzed oxidative annulation of cyclopentane-1,2-dione, 2-aminopyridine, and alkynes afforded 4,5-dihydrocyclopenta[b]pyrrol-6(1H)ones. [98] 2-Aminopyrimidine was also introduced (compound 78) as an easily installable and readily remov- [84][85][86][87] Scheme 5. General synthetic approaches to cyclopentenoneannelated five-membered heterocycles.…”

“…[153] Transformation of the acid into the acyl chloride with subsequent cyclization produced 4H-indeno[1,2-b]thiophen-4-one 200. A catalytic route to this compound via carbonylation and reaction with 2-thienylboronic acid was proposed by Song et al, [154] and Pd-catalyzed cyclizations of chloro-substituted benzoylthiophenes [84,85] were also studied (Scheme 31). The target compound 201 was obtained in high yields by the Wolff-Kishner reduction of ketone 200.…”

“…Synthesis of 4H-indeno[1,2-b]thiophene 201. [84,85,[149][150][151][152][154][155][156] Scheme 32. Preparation of substituted 4H-indeno[1,2-b] thiophene derivatives.…”

Synthesis of Pyrazolo-Fused 4-Azafluorenones in an Ionic Liquid. Mechanistic Insights by Joint Studies Using DFT Analysis and Mass Spectrometry

“…They are also used in the treatment of hyperlipoproteinemia and neurodegenerative diseases [4], and present anticancer activity [7]. Indenopyridine scaffold (I) is active against Candida albicans in micro molar concentrations [8], polifothine (II) is an anti-cholinergic alkaloid obtained from Polyalthia longifolia [9,10], indenoquinoline (III) shows antibacterial activity against Gram-positive and Gram-negative bacteria [11] and TAS-103 (IV) antitumor activity [12] (Figure 1). The main methodology reported for the synthesis of indeno [1,2-b]-pyrazolo [4,3-e]pyridines (IPP) includes the reaction between amino-aromatic or heteroaromatic substrates (1), aromatic or aliphatic aldehydes (2), and 1,3-indanedione (3) using conventional and unconventional methods [13] (Table 1), where 5-amino-pyrazoles are the most studied heterocyclic amines in this strategy.…”