A simple access to triarylmethane derivatives from aromatic aldehydes and electron-rich arenes catalyzed by FeCl3

A new practical synthesis of triaryl and trisindolylmethanes under solvent-free reaction conditions

“…Heterogeneous solid Brønsted acid catalysts include silica gel-supported NaHSO 4 , 20 polystyrene-supported sulfonic acid, 21 silica sulfuric acid, 22 perfluorinated sulfonic acid resin (Nafion-H). 23 Unsymmetrical TRAMs have been prepared using ZnBr 2 /SiO 2 and AcBr, 24 whilst symmetrical and unsymmetrical TRAMs using FeCl 3 /Ac 2 O: 25 the reaction mechanisms involves the in situ formation of an α-bromobenzyl acetate or a geminal diacetate, respectively, as the reactive intermediate species.…”

Lewis‐Acid‐Mediated Domino Reactions of Bis(diacetoxymethyl)‐Substituted Arenes and Heteroarenes

“…Coupling constants (J) are reported in Hz. Carbon types were determined from 13 C NMR experiments. Elemental analyses were performed with a Perkin-Elmer series II 2400 (IIT Madras) elemental analyzer.…”

“…An easy access to the triarylmethane derivatives has been achieved by the reaction of aromatic aldehydes with arenes in the presence of FeCl 3 and acetic anhydride. [13] Kodomari et al reported [14] a convenient synthesis of 9,10-diarylanthracenes by the reaction of aromatic aldehydes and arenes in the presence of acetyl bromide and 569 mination followed by electrocyclohetero-arylated intermediate may lead to the formation of bis-arylated 1,1-diacetates, which on cyclization followed by aromatization furnish annulated heterocycles.…”

H3PW12O40‐Catalysed Alkylation of Arenes and Diveratrylmethanes: Convenient Routes to Triarylmethanes and to Symmetrical and Unsymmetrical 9,10‐Diaryl‐2,3,6,7‐tetramethoxyanthracenes

“…Vicarious nucleophilic substitution of hydrogen [2] and addition of arylboronic acids to aldehydes catalysed by cationic Pd II /bipyridine, [3] as well as Friedel-Crafts alkylation of arenes with aldehydes catalysed variously by trifluoromethanesulfonic acid or trifluoroacetic acid, [4] Cu(OTf) 2 , [5] sulfuric acid, [6] InCl 3 /chloromethylsilane, [7] [Ir(COD)Cl] 2 -SnCl 4 , [8] Yb(OTf) 3 , [9] FeCl 3 [10] and ZnBr 2 /SiO 2 /AcBr [11] have been reported for the synthesis of TRAMs. These compounds are also synthesized through the alkylation of electron-rich arenes with (3-indolyl)methanamines in the presence of chiral Brønsted acids, [12a] double Friedel-Crafts reactions of indoles and 2-formylbiphenyls catalysed by chiral phosphoric acids, [12b] alkylation of α-(3-indolyl)benzylamines with N-methylindole catalysed by Brønsted acids, [12c] palladium-catalysed direct arylation of aryl(azaaryl)methanes with aryl halides, [13a] Suzuki-Miyaura coupling of diarylmethyl carbonates with arylboronic acids [13b] and by benzylation/[3+3] cyclocondensation in the presence of FeCl 3 .…”