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Electrochemical Generation of I+. Typical Procedure. The anodic oxidation was carried out in an H-type divided cell (4G glass filter) equipped with a platinum plate anode and cathode (40 mm x 20 mm). In the anodic chamber was placed a solution of iodine (127 mg, 0.500 mmol) in 0.3 M Bu4NBF4/CH3CN (8.0 mL). In the cathodic chamber were placed 0.3 M Bu4NBF4/CH3CN (8.0 mL) and trifluoromethanesulfonic acid (79 mg, 0.526 mmol). The constant current electrolysis (8 mA) was carried out at 0 ? with magnetic stirring until 2.1 F/mol of electricity was consumed. A Typical Iodination Procedure Using Batch Mixing. A solution of I+(cooled at 0 ?) generated from iodine (127 mg, 0.500 m mol) by using electrochemical oxidation was added to a solution of 1,3-dimethoxybenzene (113 mg, 0.818 m mol) in CH3CN (8 mL, cooled at 0 ?) by syringe. (At this time the solutions of I+was quickly transferred to syringes, which were kept cool with dry ice, and immediately usued. Decomposition of I+ was thus avoided.) The reaction mixture was stirred for 1 h at 0 ?. The solvent was removed under reduced pressure. The Supplementary Material (ESI) for Chemical Communications residue was quickly filtered through a short column (10 cm) of silica gel to remove Bu4NBF4. The silica gel was washed with ether (100 mL). The solvent was removed under reduced pressure and the residue was dissolved in hexane (50 mL). The organic phase was washed with sat. NaHCO3 (30 mL) and then was separated. The solvent was removed to give a crude mixture (179.4 mg). Yields of 4-iodo-1,3-dimethoxybenzene (monoiodo product) and 4,6-diiodo-1,3- dimethoxybenzene (diiodo product) were determined by GC analysis: 4-iodo-1,3-dimethoxybenzene 45% (96.8 mg, 0.367 m mol, t R 9.75 min, column, CBP-1; 0.22 mm f x 0.25 µm x 25 m; oven temperature, 100 ?; rate of temperature increase, 10 ?/min): 4,6-diiodo-1,3- dimethoxybenzene 18% (58.0 mg, 0.149 m mol, t R 14.3 min, column, CBP-1; 0.22 mm f x 0.25 µm x 25 m; oven temperature, 100 ?; rate of temperature increase, 10 ?/min). A Typical Iodination Procedure Using Micromixing. A solution of 1,3-dimethoxybenzene (112 mg, 0.811 m mol) in CH3CN and an I+ solution (8 mL, cooled at 0 ?), generated from I2 (127 mg, 0.500 m mol) using the electrochemical method described above, were simultaneously introduced to an IMM single mixer (version 2) having a Si inlet (channel width = 50 µm), which was dipped in a coolant at 0 ?, using syringe pumps (flow rate is 3.0 mL/min each). Then, the reaction mixture coming out from the outlet of the micromixer was collected with a 100 mL round bottom flask, containing sat. NaHCO3 (30 mL), sat. NaS2O3 (1 mL), and Et2O (30 mL), with magnetic stirring. The organic layer was separated and the solvent was removed under reduced pressure. The residue was quickly filtered through a short column (10 cm) of silica gel to remove Bu4NBF4. The silica gel was washed with Et2O (100 mL). The solvent was removed under reduced pressure and the residue was dissolved in hexane (50 mL). The organic phase was washed with sat. NaHCO3 (30 mL) and then was separated. The solvent was removed to give a crude product (204 mg). Yields of 4-iodo-1,3-dimethoxybenzene (monoiodo product) and 4,6-diiodo-1,3- dimethoxybenzene (diiodo product) were determined by GC analysis: 4-iodo-1,3-dimethoxybenzene 78% (167 mg, 0.632 m mol): 4,6-diiodo-1,3- dimethoxybenzene 4% (13 mg, 0.033 m mol). Frankie is the freelance writer for e-commerce website in the chemistry. Guidechem.com is just a place for you to look for some chemicals. Our guidechem provide the most convenient conditions for the international buyers and let these leads benefit all the business people.
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