Amberlyst-15/[Bmim][PF₆] Catalyzed Synthesis of C₃-Symmetric Triarylbenzenes via Cyclotrimerization of Alkynes

Abstract

The construction of C 3 -symmetric triarylbenzenes via cyclotrimerization of alkynes using Amberlyst-15/1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF 6 ] has been developed. The catalytic system works well for various substrates under milder reaction conditions. The developed methodology is operationally simple, and metal-free, solvent-free, and additive-free reactions with excellent yields make it good for synthetic utility. The recyclability of the Amberlyst-15/[Bmim][PF 6 ] as well as 100% atom efficiency makes the developed protocol more green.

Facile Synthesis of 1,3,5‐Triarylbenzenes and 4‐Aryl‐NH‐1,2,3‐Triazoles Using Mesoporous Pd‐MCM‐41 as Reusable Catalyst

“…4,4′′‐Dimethoxy‐5′‐(4‐methoxyphenyl)‐1,1′:3′,1′′‐terphenyl (2b): (Table ): White solid (130.84 mg, 99 %). 1 H NMR (400 MHz, CDCl 3 ): δ = 7.65 (s, 3 H),7.61 (d, J = 8.8 Hz, 6 H), 7.00 (d, J = 8.0 Hz, 6 H), 3.84 (s, 9 H); 13 CNMR (100 MHz, CDCl 3 ): δ = 159.3, 141.9, 133.9, 128.4, 123.9, 114.3, 55.4.…”

“…4,4′′‐Dimethyl‐5′‐( p ‐tolyl)‐1,1′:3′,1′′‐terphenyl (2c): (Table ): White solid (113.84 mg, 98 %). 1 H NMR (500 MHz, CDCl 3 ): δ = 7.73 (s, 3 H), 7.59 (d, J = 8.0 Hz, 6 H), 7.28 (d, J = 8.0 Hz, 6 H), 1.54 (s, 9 H).…”

“…[18] The above procedure was followed to prepare the other 1,3,5-triphenylbenzene derivatives 2b-2t from their respective starting materials. -5′-(4-methoxyphenyl)-1,1′:3′,1′′-terphenyl (2b): (Table 3): [18] White solid (130.84 mg, 99 %). 1 3, 141.9, 133.9, 128.4, 123.9, 114.3, 55.4.…”

“…1 3, 141.9, 133.9, 128.4, 123.9, 114.3, 55.4. -5′-(p-tolyl)-1,1′:3′,1′′-terphenyl (2c): (Table 3): [18] White solid (113.84 mg, 98 %). 1 3, 138.6, 137.4, 129.7, 127.3, 124.7, 21.3.…”

“…1 3, 138.6, 137.4, 129.7, 127.3, 124.7, 21.3. (Table 3): [18] White solid (135.21 mg, 99 %). 1 -5′-(4-bromophenyl)-1,1′:3′,1′′-terphenyl (2e): (Table 3): [18] White solid (177.41 mg, 98 %).…”