4,5-Difluorophthalonitrile synthesis

Yield:134450-56-9 87%

Reaction Conditions:

with 1,1'-bis(diphenylphosphanyl)ferrocene;tris-(dibenzylideneacetone)dipalladium⁽⁰⁾ in N,N-dimethyl acetamide at 100; for 4 h;

Steps:

1 (Synthesis Example 1) 4,5-difluorophthalonitrile

Dissolve 1,2-dibromo-4,5-difluorobenzene (12.0 g, 44.14 mmol) in 40.0 mL of dimethylacetamide in a 200 mL glass culture tube with a magnetic stirrer.After adding polymethylhydrosiloxane (0.960 mL) at room temperature, Pd₂(dba)₃(432 mg, 0.474 mmol 1.0 mol%) and dppf (360 mg, 0.648 mmol 1.35 mol%) are added at that temperature.Zn(CN)₂(10.4 g, 88.28 mmol 2.0 equiv.) is added at a time.The reaction mixture was stirred at 100 °C for 4 h, and then cooled to room temperature.After diluting the reaction mixture with dichloromethane, the solid precipitate is filtered using a pad of diatomaceous earth and silica gel, followed by extraction using water and dichloromethane.The organic layers were collected and washed with a saturated aqueous NaCl solution, and then anhydrous Na-₂SO₄was added to remove the remaining water.Filter the desiccant through a glass filter and remove as much solvent as possible using a rotary evaporator.Hex : EtOAc = 4 : 1 (R_f=0.34) was purified by column chromatography using a developing solution, and recrystallized from hexane to obtain a cleaner compound to obtain a white solid;6.36 g (38.75 mmol, 87%)

References:

KR2022/97091,2022,A Location in patent:Paragraph 0176-0181