Ethyl 5-broMo-2-furoate, 97+%

To a stirred suspension of 5-bromo-2-furoic acid (15.0 g, 78.54 [MMOL)] in 225 mL of CH2CI2 at room temperature was added [OXALYL] chloride followed by a catalytic amount of N, N'-dimethylforamide. After 1 h, ethanol (20 mL) was added followed by [TRIETHYLAMINE (22 ML).] Reaction was continued for 15 h. The mixture was concentrated under reduced pressure to a residue, which was extracted with excess volume of hexanes, and [HEXANES-CH2CI2 (3] : 1, v/v). The extracts were filtered, the filtrated was concentrated to a yellow oil, dried on high vacuum, yielding 17.2 g (93percent) of the desired ester.To a suspension of 5-bromo-2-furoic acid (15g) in CH2CI2 (275moi) at room temperature was added oxalyl chloride (6. 9ml) followed by a catalytic amount of N, N'- dimethylformamide (0.3ml). The mixture was stirred for 1 hr, whereupon, EtOH (20moi) and TEA (22ml) were added and then let stir overnight. The mixture was concentrated in vacuo and extracted with hexanes and hexanes/CH2CI2. The extracts were concentrated in vacuo to give an oil (17. 2g, 93percent).Compound 3 (5 . 37 g, 30 mmol) dissolved in 100 ml of ethanol in the solvent, by adding 2 ml of concentrated sulfuric acid, heated to 80 degree Celcius reflux reaction for 12 hours, concentrated under reduced pressure to remove the solvent, is added to the remaining reaction mixture in 100 ml of ice water, and saturated sodium carbonate solution to adjust the pH to 7 - 8, ethyl acetate extraction reaction solution three times, the combined organic phase after washing with saturated sodium chloride solution, dried with anhydrous sodium sulfate. The solvent is removed under reduced pressure, vacuum drying to obtain compound 4 b (5 . 32 g, 24.3 mmol), yield 81percent.To a stirred suspension of 5-bromo-2-furoic acid (15.0 g, 78.54 mmol) in 225 mL of CH2Cl2 at room temperature was added oxalyl chloride followed by a catalytic amount of N, N?-dimethylforamide. After 1 h, ethanol (20 mL) was added followed by triethylamine (22 mL). Reaction was continued for 15 h. The mixture was concentrated under reduced pressure to a residue, which was extracted with excess volume of hexanes, and hexanes-CH2Cl2 (3:1, v/v). The extracts were filtered, the filtrated was concentrated to a yellow oil, dried on high vacuum, yielding 17.2 g (93percent) of the desired ester.To a stirred suspension of 5-bromo-2-furoic acid (15.0 g, 78.54 mmol) in 225 mL of CH2C12 at room temperature was added oxalyl chloride followed by a catalytic amount of N, N'-dimethylforamide. After 1 h, ethanol (20 mL) was added followed by triethylamine (22 mL). Reaction was continued for 15 h. The mixture was concentrated under reduced pressure to a residue, which was extracted with excess volume of hexanes, and hexanes-CH C12 (3:1, v/v). The extracts were filtered, the filtrated was concentrated to a yellow oil, dried on high vacuum, yielding 17.2 g (93percent) of the desired ester.Intermediate 1: S-Bromo-furan-l-carboxylic acid ethyl ester A solution of 5-bromofuran-2-carboxylic acid (2 g) in ethanol (15 ml) was treated with cone, sulphuric acid (2 drops) and heated to reflux overnight. The mixture was then To a stirred suspension of 5-bromo-2-furoic acid (15.0 g, 78.54 [MMOL)] in 225 mL of CH2CI2 at room temperature was added [OXALYL] chloride followed by a catalytic amount of N, N'-dimethylforamide. After 1 h, ethanol (20 mL) was added followed by [TRIETHYLAMINE (22 ML).] Reaction was continued for 15 h. The mixture was concentrated under reduced pressure to a residue, which was extracted with excess volume of hexanes, and [HEXANES-CH2CI2 (3] : 1, v/v). The extracts were filtered, the filtrated was concentrated to a yellow oil, dried on high vacuum, yielding 17.2 g (93percent) of the desired ester.To a suspension of 5-bromo-2-furoic acid (15g) in CH2CI2 (275moi) at room temperature was added oxalyl chloride (6. 9ml) followed by a catalytic amount of N, N'- dimethylformamide (0.3ml). The mixture was stirred for 1 hr, whereupon, EtOH (20moi) and TEA (22ml) were added and then let stir overnight. The mixture was concentrated in vacuo and extracted with hexanes and hexanes/CH2CI2. The extracts were concentrated in vacuo to give an oil (17. 2g, 93percent).Compound 3 (5 . 37 g, 30 mmol) dissolved in 100 ml of ethanol in the solvent, by adding 2 ml of concentrated sulfuric acid, heated to 80 degree Celcius reflux reaction for 12 hours, concentrated under reduced pressure to remove the solvent, is added to the remaining reaction mixture in 100 ml of ice water, and saturated sodium carbonate solution to adjust the pH to 7 - 8, ethyl acetate extraction reaction solution three times, the combined organic phase after washing with saturated sodium chloride solution, dried with anhydrous sodium sulfate. The solvent is removed under reduced pressure, vacuum drying to obtain compound 4 b (5 . 32 g, 24.3 mmol), yield 81percent.The furoic acid (lg, 0.526ml) was added ethanol (600 mL) was added and stirred, warmed to 70 ° C until complete dissolution at reflux, A solution of thionyl chloride (188 g, 1.579 mol) was added dropwise over 4 hours and the reaction was continued for 4 hours.Concentrated by rotary evaporation to recover ethanol.The remaining concentrate was diluted with water and extracted with n-hexane (3 x 300 mL). The organic phases were combined and washed with 5percent sodium carbonate solution and saturated brine, dried over anhydrous sodium sulfate, filtered, The filtrate was concentrated by rotary evaporation to give pure 5-bromo-2-furoate.

Molecular Weight:219.03
XLogP3:2.2
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:3
Exact Mass:217.95786
Monoisotopic Mass:217.95786
Topological Polar Surface Area:39.4
Heavy Atom Count:11
Complexity:149
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes