methyl 5-nitro-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzoate synthesis

Yield:1393477-19-4 37.6%

Reaction Conditions:

with (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride;potassium acetate in 1,4-dioxane at 70; for 3 h;

Steps:

61 Synthesis of Compound 61.2.

Bis (pinacolate) diborate (0.9 g, 3.46 mmol, 1.0 eq), PdCl₂(dppf) (0.277 g, 0.346 mmol, 0.1 eq) and AcOK (1.018 g, 10.38 mmol, 3.0 eq) were dissolved in 1,4-dioxane (10 mL).
Suspension was degassed using argon, then a solution of 61.1 (0.9 g, 3.46 mmol, 1.0 eq) in 1,4-dioxane (8.0 mL) was added.
Reaction mixture was stirred at 70° C. for 3 hours.
After completion of reaction, solids were filtered and solvents were removed under reduced pressure.
The crude was suspended in water then extracted with extracted with EtOAc.
Organic layers were combined, washed with brine solution, dried over Na₂SO₄ and concentrated under reduced pressure to obtain crude which was purified by column chromatography to furnish 61.2 (0.40 g, 37.6%).

References:

US2016/251376,2016,A1 Location in patent:Paragraph 0821; 0822; 0823