86% |
With phosphorus tribromide; In water; toluene; at 0 - 90℃; for 7.25h;Inert atmosphere; |
To a stirred solution of 2-(2, 5-dibromophenoxy)ethan-1-ol (910.0 g, 3.07 mol) in toluene (6370 mL), PBr3 (Aldrich, 145 mL, 1.54 mol) was added under nitrogen atmosphere at 0 C over 15 min. The resulting mixture was heated at 90 C for 4 h and then cooled to 0 C. PBr3 (13.57 mL, 142.92 mmol) was added followed by the slow addition of water (20 mL) and heating was continued at 90 C for 3 h. Completion of the reaction was monitored by TLC, the reaction mixture was then cooled to 10 C and quenched with 1 N NaOH solution (2200 mL). The milky solid layer, formed immediately after quenching, was filtered through celite pad. The organic layer was separated, washed with water (1820 mL), brine solution (1820 mL) and dried over anhydrous Na2S04. It was then evaporated at 45 C under vacuum. The resulting crude material was dissolved in EtOAc (3185 mL), the organic layer was washed with water (1820 mL), brine solution (1820 mL) and dried over anhydrous Na2S04. The organic layer was evaporated at 40 C under reduced pressure to afford the title compound. Yield: 86% (946 g, white solid). 1H NMR (400 MHz, DMSO-d6 ): delta 7.54 (d, J = 8.4 Hz, 1 H), 7.36 (d, J = 1.6 Hz, 1 H), 7.13-7.10 (m, 1 H), 4.45 (t, J = 1.2 Hz, 2H), 3.82 (t, J = 1.6 Hz, 2H). HPLC: (Method A) Rt. 4.7 min, 93.0% (Max). |
86% |
With phosphorus tribromide; In water; toluene; at 0 - 90℃; for 7.25h;Inert atmosphere; |
To a stirred solution of 2-(2, 5-dibromophenoxy)ethan-1-ol (910.0 g, 3.07 mol) in toluene (6370ml), PBr3 (Aldrich, 145 ml, 1.54 mol) was added under nitrogen atmosphere at 0 oc over 15min. The resulting mixture was heated at 90 oc for 4 h and then cooled to 0 C. PBr3 (13.57 ml,142.92 mmol) was added followed by the slow addition of water (20 ml) and heating was continued at 90 oc for 3 h. Completion of the reaction was monitored by TLC, the reactionmixture was then cooled to 10 oc and quenched with 1 N NaOH solution (2200 ml). The milkysolid layer, formed immediately after quenching, was filtered through celite pad. The organiclayer was separated, washed with water (1820 ml), brine solution (1820 ml) and dried overanhydrous Na2S04 . It was then evaporated at 45 oc under vacuum. The resulting crude material was dissolved in EtOAc (3185 ml), the organic layer was washed with water (1820 ml), brinesolution (1820 ml) and dried over anhydrous Na2S04 . The organic layer was evaporated at 40oc under reduced pressure to afford the title compound. Yield: 86% (946 g, white solid). 1HNMR (400 MHz, DMSO-d6): o 7.54 (d, J= 8.4 Hz, 1H), 7.36 (d, J= 1.6 Hz, 1H), 7.13-7.10 (m,1 H), 4.45 (t, J = 1.2 Hz, 2H), 3.82 (t, J = 1.6 Hz, 2H). HPLC: (Method A) Rt. 4.7 min, 93.0% (Max). |
86% |
With phosphorus tribromide; In toluene; at 0 - 90℃; for 7h;Inert atmosphere; |
To a stirred solution of 2-(2,5-dibromophenoxy) ethan-1-ol (910.0 g, 3.07 mol) in toluene (6370 mL), PBr3 (Aldrich, 145 mL, 1 .54 mol) was added under nitrogen atmosphere at 0 C over 15 min. The resulting mixture was heated at 90 C for 4 h and then cooled to 0 C. PBr3 (13.57 mL, 142.92 mmol) was added followed by the slow addition of water (20 mL) and heating was continued at 90 C for 3 h. Completion of the reaction was monitored by TLC, the reaction mixture was then cooled to 10 C and quenched with 1 N NaOH solution (2200 ml_). The milky solid layer, formed immediately after quenching, was filtered through celite pad. The organic layer was separated, washed with water (1820 ml_), brine solution (1820 mL) and dried over anhydrous Na2SC>4. It was then evaporated at 45 C under vacuum. The resulting crude material was dissolved in EtOAc (3185 mL), the organic layer was washed with water (1820 mL), brine solution (1820 mL) and dried over anhydrous Na2SC>4. The organic layer was evaporated at 40 C under reduced pressure to afford the title compound. Yield: 86% (946 g, white solid). 1H NMR (400 MHz, DMSO -ofe): d 7.54 (d, J = 8.4 Hz, 1 H), 7.36 (d, J = 1.6 Hz, 1 H), 7.13-7.10 (m, 1 H), 4.45 (t, J = 1.2 Hz, 2H), 3.82 (t, J = 1.6 Hz, 2H). HPLC: (Method A) Rt. 4.7 min, 93.0% (Max). |
86% |
With phosphorus tribromide; In toluene; at 0 - 90℃; for 4.25h;Inert atmosphere; |
To a stirred solution of 2-(2, 5-dibromophenoxy) ethan-1 -ol (910.0 g, 3.07 mol) in toluene (6370 mL), PBr3 (Aldrich, 145 mL, 1.54 mol) was added under nitrogen atmosphere at 0 C over 15 min. The resulting mixture was heated at 90 C for 4 h and then cooled to 0 C. PBr3 (13.57 mL, 142.92 mmol) was added followed by the slow addition of water (20 mL) and heating was continued at 90 C for 3 h. Completion of the reaction was monitored by TLC, the reaction mixture was then cooled to 10 C and quenched with NaOH solution (1 N, 2200 mL). The milky solid layer, formed immediately after quenching, was filtered through celite pad. The organic layer was separated, washed with water (1820 mL), brine solution (1820 mL) and dried over anhydrous Na2S04. It was then evaporated at 45 C under vacuum. The resulting crude material was dissolved in EtOAc (3185 mL), the organic layer was washed with water (1820 mL), brine solution (1820 mL) and dried over anhydrous Na2S04. The organic layer was evaporated at 40 C under reduced pressure to afford the title compound. Yield: 86% (946 g, white solid). 1H NMR (400 MHz, DMSO -<): d 7.54 (d, J = 8.4 Hz, 1 H), 7.36 (d, J = 1.6 Hz, 1 H), 7.13-7.10 (m, 1 H), 4.45 (t, J = 1.2 Hz, 2H), 3.82 (t, J = 1.6 Hz, 2H). HPLC: (Method A) Rt. 4.7 min, 93.0% (Max). |
65.2% |
With phosphorus tribromide; In toluene; at 20 - 90℃; for 2.5h; |
Phosphorus tribromide (2.81 mL, 29.91 mmol) was added to a solution of <strong>[377091-17-3]2-(2,5-dibromophenoxy)ethanol</strong> (13.21 g, 44.64 mmol) in toluene (100 mL) at room temperature, and the mixture was stirred at 90C for 2.5 hr. The reaction mixture was poured into ice water (350 mL), and the mixture was extracted three times with a mixed solvent of ethyl acetate/hexane (3:1). The organic layer was washed with brine, and dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The insoluble substance was removed by filtration, and washed with a mixed solvent of ethyl acetate/hexane (1:2), and the filtrate was concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (solvent gradient; 2?8% ethyl acetate/hexane) to give 1,4-dibromo-2-(2-bromoethoxy)benzene (10.45 g, 29.1 mmol, 65.2%) as a white solid. |
34% |
With phosphorus tribromide; In toluene; at 90℃; for 3h; |
PBr3 (6.42 ml_, 68.38 mmol) was added to a solution of 2-(2,5-dibromo- phenoxy)ethanol (9.2 g, 31.08 mmol) in toluene (200 ml_). The reaction mixture was warmed up to 90 0C and allowed to react for 3 h. It was poured into H2O (200 ml_) and extracted with EtOAc (2x150 ml_). The organic layer was dried over Na2SO4 (anhydrous), filtered and concentrated. The crude residue was slurred with CH2CI2 and collected by filtration. The crude residue was purified by flash chromatography on SiO2 (20% EtOAc/hexanes) to furnish 1 ,4-dibromo-2-(2-bromoethoxy)benzene (3.84 g, white solid, yield: 34%). 1H NMR (CDCI3, 250 MHz) delta ppm: 7.4 (d, J = 8.7 Hz, 1 H), 7.02(m, 2H), 4.32 (t, J = 6.3 Hz, 2H), 3.67 (t, J = 6.5 Hz, 2H). |
99 g |
With phosphorus tribromide; In water; toluene; at 0 - 90℃; for 10h;Inert atmosphere; |
To a stirred solution of <strong>[377091-17-3]2-(2,5-dibromophenoxy)ethan-1-ol</strong> (45 g, 152 mmol) in toluene (315 mL) under inert atmosphere, PBr3 (18.47 g, 68.0 mmol) was added slowly at 0 C. The resulting mixture was heated at 90 C for 2 h. It was cooled to 0 C and PBr3 (8.2 g, 30.0 mmol) and water (0.9 mL) were added slowly and the heating was continued at 90 C for 8 h. Completion of the reaction was monitored by TLC. The reaction mixture was cooled to 10 C and quenched with 1 N NaOH solution (270 mL). The organic phase was separated and was washed with water (150 mL), brine (150 mL), dried over Na2SO4 and evaporated at 45 C under vacuum, to give the title compound. Yield: 90.8% (99 g, off white solid). 1H NMR (400 MHz, CDCI3): delta 7.43 (d, J = 8.8 Hz, 1 H), 7.05-7.02 (m, 2H), 4.34 (t, J = 6.4 Hz, 2H), 3.70 (t, J = 6.4 Hz, 2H). |
|
With phosphorus tribromide; In water; toluene; at 0 - 90℃; for 7.58h;Inert atmosphere; |
To a stirred solution of <strong>[377091-17-3]2-(2,5-dibromophenoxy)ethan-1-ol</strong> (910.0 g, 3074.0 mmol) in Toluene (6370 mL), PBr3 (Aldrich, 145 mL, 1541 mmol,) was added under nitrogen atmosphere at 0 C over 15 min and the resulting mixture was heated to 90 C for 4 h. It was then cooled to 0 C and PBr3 (13.57 mL, 142.92 mmol) was added slowly. Then water (20 mL) was added slowly over 20 min. The resulting mixture was heated for 3 h at 90 C. Completion of the reaction was monitored by TLC. The reaction mixture was cooled to 10 C and quenched with 1 N NaOH solution (2200 mL). A milky solid was formed and was filtered off through celite pad. The organic layer was separated and washed with water (1820 mL), brine solution (1820 mL), dried over sodium sulphate and evaporated at 45 C under vacuum. The resulting crude product was dissolved in ethyl acetate (3185 mL), washed with water (1820 mL), brine solution (1820 mL), dried over sodium sulphate and evaporated at 40 C under reduced pressure to give the title compound. Yield: 86% (946 g, white solid). 1H NMR (400 MHz, DMSO-d6): delta 7.54 (d, J = 8.4 Hz, 1H), 7.36 (d, J = 1.6 Hz, 1H), 7.13-7.10 (m, 1H), 4.45 (t, J = 1.2 Hz, 2H), 3.82 (t, J = 1.6 Hz, 2H). HPLC: (Method A) Rt. 4.72 min, 93.03% (Max), 92.82% (220nm). |