ChemicalBook CAS DataBase List 2,5-Difluoronitrobenzene

2,5-Difluoronitrobenzene synthesis

5synthesis methods

Product Name:2,5-Difluoronitrobenzene
CAS Number:364-74-9
Molecular formula:C6H3F2NO2
Molecular Weight:159.09

98-95-3

402-67-5

369-34-6

364-74-9

350-46-9

1493-27-2

GENERAL STEPS: In a FEP or PFA reactor fitted with a PTFE-lined magnetic stir bar and connected to a gas scrubber bottle, substituted benzene (0.95-1.10 mmol), 1,1,1,3,3-pentafluorobutane (2 mL per mL of C6H5R), and BF3-Et2O (1.3-1.5 mmol/mmol C6H5R) were added. The mixture was stirred at 0-5 °C (ice bath) for 10-15 min, followed by batchwise addition of XeF2 (1.2-1.3 mmol/mmol C6H5R). After each addition, the mixture was stirred at 22-25 °C for 3-5 min and recooled. After the addition was completed, the dark solution was continued to be stirred at 22-25 °C for 15-30 min. At the end of the reaction, the reaction was quenched by the addition of 10% aqueous KHCO3, the upper organic layer was separated and filtered through a short column packed with silica gel (40-60 μm) and subsequently dried with magnesium sulfate. The final products were analyzed by 19F NMR and GC/MS. The major products are listed in the table and the others are as follows (with GC/MS data).

540-36-3
295 suppliers
$10.00/5g

364-74-9
290 suppliers
$6.00/5g

Yield:364-74-9 83%

Reaction Conditions:

with sulfuric acid;potassium nitrate at 5;Large scale;

Steps:

1.1; 2.1 (1)nitration reaction
1400 g of p-difluorobenzene and 5800 mL of sulfuric acid were added to the reaction vessel, and the temperature was controlled at about 5 °C. 1450 g of potassium nitrate was added in portions.After the reaction is over, the GC tracks,Until the reaction is completed. After completion of the reaction, ice water was analyzed by water and suction filtered to give a white solid 2,5-difluoronitrobenzene, 1620 g, content 99%, yield 83%.

References:

Changzhou University;Chen Xingquan;Dong Yanmin CN109553534, 2019, A Location in patent:Paragraph 0014; 0021

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