Silica gel as an effective catalyst for the alkylation of phenols and some heterocyclic aromatic compounds

Antioxidant Effects of Quinoline Alkaloids and 2,4-Di-tert-butylphenol Isolated from Scolopendra subspinipes

“…[12][13][14] The active fraction (Fr. 6, 40 mg) from the first column was subjected to preparative TLC (Silica gel 60 F 254 , Merck) with TBARS Assay The LDL oxidation was determined spectrophotometrically by measuring the amount of TBARS.…”

“…Compounds 1 and 2 were determined to be 3,8-dihydroxyquinoline and 2,4-di-tertbutylphenol, respectively, by comparing their physicochemical and spectroscopic data with that reported in the literature. 3,[12][13][14] Compound 3 has a molecular formula of C 11 Compounds 1-3 were assayed for antioxidant activity by various assay methods, such as TBARS assay, conjugated diene formation, REM, and fragmentation of apoB-100 on copper-mediated LDL-oxidation. Also, compounds 1-3 were tested for their radical DPPH scavenging activity and metal chelating activity to confirm the mechanism responsible for the antioxidant activity.…”

Palladium(0)-Catalyzed Synthesis of 2-Vinyl-2,3-dihydro-benzo[1,4]dioxins

“…[28] Ϫ Optical rotations were deterethyl acetate, 3:1 (19.6 mg, 0.02 mmol) and dppb benzophenone. The following compounds were prepared according (34.5 mg, 0.08 mmol) in THF (5 mL) was added to a degassed mixto literature procedures: but-3-en-1,2-diol, [31] (Z)-1,4-bis(methoxyture of 3-methoxybenzene-1,2-diol (9c) (150 mg, 1.07 mmol) and carbonyloxy)but-2-ene (2a), [32] 4-N-acetylaminobenzene-1,2-diol (Z)-1-benzyloxy-4-(methoxycarbonyloxy)but-2-ene (253 mg, (6b), [33] 3-tert-butylbenzene-1,2-diol (9b), [34] 3-nitrobenzene-1,2-1.07 mmol), in THF (2 mL). After being stirred for 12 h at 25°C, diol (9c), [34] (Z)-4-(methoxycarbonyloxy)but-2-en-1-ol, [35] (Z)-4-the solvent was evaporated and the residue was separated by chromethoxycarbonyloxy)-1-benzyloxybut-2-ene [36] and (1R,2R)-1,2-matography on silica to give 51 mg of compound 14 as an oil bis-N-[2Ј-(diphenylphosphanyl)benzoyl]-1,2-diaminocyclo-(16%); R f 0.54 (eluent: petroleum ether/diethyl ether, 1:1.5).…”

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

“…[6a] : 70-72°C 4-tert-Butylphenol (2g): [19] Obtained by following the general procedure for Table 2 using 1-tert-butyl-4-iodobenzene (0.18 mL, 1.0 mmol), then purified by column chromatography (SiO 2 ; CH 2 Cl 2 ) to afford 2g as a white solid (100 mg, 67 % yield); m.p. 96-98°C (ref.…”

“…96-98°C (ref. [19] 96-100°C 3-Methylphenol (2h): [9] Obtained by following the general procedure for Table 2 [9] Obtained by following the general procedure for Table 2 Phenol (2j): [9] Obtained by following the general procedure for Table 2 using iodobenzene (0.11 mL, 1.00 mmol), then purified by column chromatography (SiO 2 ; CH 2 Cl 2 ) to give 2j as a colorless solid (86.3 mg, 92 % yield); m.p. 36-38°C (ref.…”