Synthesis of CuO on mesoporous silica and its applications for coupling reactions of thiols with aryl iodides

Abstract

Novel CuO on mesoporous silica is prepared under a convenient approach, and has been shown to be an efficient catalyst for cross-coupling reactions of thiols with aryl iodides with only 1.0-5.0 mol% catalyst loading.

Green Catalysts Derived from Agricultural and Industrial Waste Products: The Preparation of Phenols from CsOH and Aryl Iodides using CuO on Mesoporous Silica

“…The product was obtained in good to excellent yields by using this catalyst system. Interestingly, catalyst A (Cu/silica = 1:20) was not only reactive for C-S coupling reactions; [13] but was also suitable for C-O coupling reactions, affording the target in 87 % yield (Table 1, entry 1). It is important to note that catalyst D (Cu/silica = 1:5) gave the best result, yielding the product in 94 % isolated yield (Table 1, entry 4).…”

“…s, 1 H), 6.76 (d, J = 8.0 Hz, 2 H), 7.18 (d, J = 8.0 Hz, 2 H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ = 116.6, 125.7, 129.5, 153.8 ppm.…”

“…s, 1 H), 6.83 (d, J = 7.6 Hz, 2 H), 6.91 (t, J = 7.6 Hz, 1 H), 7.20 (t, J = 7.6 Hz, 2 H) ppm. 13 C NMR (100 MHz, CDCl 3 ): δ = 115.3, 120.9, 129.7, 155.0 ppm. [20] Obtained by following the general procedure for Table 2 using CsOH/H 2 O (672 mg, 4.0 mmol) and 3-iodophenol (220.0 mg, 1.0 mmol), then purified by column chromatography (SiO 2 ; hexane/EtOAc, 2:1) to give 2k as a white solid (96.8 mg, 88 % yield); m.p.…”

“…[13] Distinct from our previous report, we were determined to find a greener catalytic system that could be used to prepare phenols. In fact, we demonstrate here that these greener catalysts show better catalytic performance than the catalyst that was used previously in the C-S coupling reaction.…”

“…In fact, we demonstrate here that these greener catalysts show better catalytic performance than the catalyst that was used previously in the C-S coupling reaction. [13] Rice husks or tion of CsOH with aryl iodides. Low catalyst loading (1 mol-%) without the need for ancillary ligands make these very attractive "green" catalysts.…”