Regioselective Arylations of α‐Amido Sulfones with Electron‐Rich Arenes through Friedel–Crafts Alkylations Catalyzed by Ferric Chloride Hexahydrate: Synthesis of Unsymmetrical and Bis‐Symmetrical Triarylmethanes

Abstract

Ferric chloride hexahydrate is a highly efficient catalyst for the regioselective arylation of α-amido sulfones. The products undergo further Friedel-Crafts alkylations with hetero-

Bi(OTf)3-Catalyzed One-Step Catalytic Synthesis of N-Boc or N-Cbz Protected α-Branched Amines

“…Bis [(5-ethyl)-2-thienyl] 3, 144.4, 143.5, 128.03, 127.95, 126.6, 125.1, 122.2, 47.5, 23.1, 15.4; IR (film): ν max 1600,1493,1452,1377,1316,1260,1220,1074,1015,945,802 7,134.2,131.4,128.8,128.7,127.1,107.4,104.3,44.5,21.1,13.8;IR (film): ν max 3164 (N-H), 1688,1584,1495,1404,1329,1275,1228,1035,958,764 9,129.0,128.5,127.3,126.5,123.9,122.2,120.2,119.8,119.5,111.4,40.5;: ν max 3414 (N-H), 1601,1492,1456,1417,1337,1265,1217,1152,1093,1010,793,743 …”

Amberlyst‐15 as a Green and Efficient Reusable Catalyst for Friedel‐Crafts Alkylation of Activated Arenes with N‐Sulfonyl Aldimines and Synthesis of Bis‐triarylmethanes

“…The Friedel−Crafts reaction is one of the most commonly employed methods for the synthesis of bis‐triarylmethanes, which involves the reaction of diarylmethanol or α‐amido sulfones or N ‐sulfonyl aldimines or aldehydeds with activated arenes in the presence of an acid catalyst or Lewis acid . Recently, transition metal‐catalysed routes have emerged as an alternative methods to address these issues and provide structurally diverse triarylmethanes.…”

“…Subsequently p ‐tolylsulfanimide was eliminated from II by proton of 7 to the oxonium ion intermediate ( III) . The oxonium ion III then reacts with 1,3,5‐trimethoxybenzene ( 6 a ) result in the formation of triarylmethane 8 a …”

K2S2O8-Activated Friedel–Crafts Type Alkylation of Indoles with α-Amido Sulfones

“…Dichloromethane as reaction solvent gave a slightly lower yield than toluene (entry 7). Acetonitrile, THF, and DMF as the solvents resulted in a modest yield (entries [8][9][10]. However, water as the solvent gave only a trace amount of the desired product (entry 11).…”