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ChemicalBook CAS DataBase List 1,4-DIBROMO-2,3-DIFLUOROBENZENE
156682-52-9

1,4-DIBROMO-2,3-DIFLUOROBENZENE synthesis

3synthesis methods
867366-94-7 Synthesis
(2,3-difluoro-1,4-phenylene)bis(triMethylsilane)

867366-94-7
14 suppliers
$956.12/5g

-

Yield:156682-52-9 90%

Reaction Conditions:

with bromine in tetrahydrofuran at 0 - 60; for 12 h;Solvent;

Steps:

2.4.7. Synthesis of 2,3-difluoro-1,4-dibromobenzene (10)
To a solution of compound 9 (26 g, 98.7 mmol) in 10 mL THF, bromine (14.8 mL, 296.0 mmol) in 10 mL THF was added dropwise at 0 °C. The reaction mixture was stirred for 12 h at 60 °C and slowly poured into saturated NaHSO3 solution at 0 °C. After extraction with 200 mL of CHCl3, the organic phase was washed with 3 x 50 mL of water and dried over MgSO4. After removing the organic solvent under reduced pressure, the residue was purified by flash chromatography to give 24.1 g (90%) of compound 10. 1H NMR (300 MHz, CDCl3): δ (ppm) 7.22 (s, 2H); 13C NMR (75 MHz, CDCl3): δ (ppm) 148.7 (dd, 1JC-F = 254.9 and 2JC-F = 17.3 Hz), 128.3. 109.5 (dd, 2JC-F = 10.4 Hz and 3JC-F = 8.1 Hz). HRMS (m/z, EI+) calcd for C6H2Br2F2 269.8490, found 269.8491.

References:

Jeong, Ina;Chae, Sangmin;Yi, Ahra;Kim, Juae;Chun, Ho Hwan;Cho, Jung Hyeong;Kim, Hyo Jung;Suh, Hongsuk [Polymer,2017,vol. 109,p. 115 - 125]

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