4-(tetramethyl-1,3,2-dioxaborolan-2-yl)-1,3-benzothiazole synthesis

Yield:1352796-64-5 56%

Reaction Conditions:

with palladium (II) [1,1'-bis(diphenylphosphanyl)ferrocene] dichloride;anhydrous potassium acetate in 1,4-dioxane at 80 - 110; for 19 h;Sealed tube;

Steps:

13 4-(4,4,5,5-Tetramethyl-l,3,2-dioxaborolan-2-yl)-l,3-benzothiazole

Potassium acetate (500 mg, 5.09 mmol), 4-bromo- 1,3 -benzothiazole (365 mg, 1.70 mmol), and bis(pinacolato)diboron (662 mg, 2.61 mmol) are added to a vial. 1,4- Dioxane (11 mL) is added under nitrogen and the mixture is purged with nitrogen for 10 minutes. [l,r-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (134 mg, 0.18 mmol) is added in one portion and the vial is sealed. The mixture is stirred at 110 °C for one hour and then at 80 °C for 18 hours. The reaction mixture is cooled to ambient temperature and filtered through a pad of diatomaceous earth. The filtrate is concentrated in vacuo and purified via silica gel flash chromatography eluting with 0-100% EtOAc/hexanes to give the title compound (386 mg, 56%). 'H NMR (DMSO-d6) 6 9.43 (1H, s,), 8.30 (dd, J= 8.0, 1.0 Hz, 1H), 7.83 (dd, J= 7.0, 1.0 Hz, 1H), 7.48 (t, J= 7.5 Hz, 1H), 1.34 (s, 12H).

References:

WO2022/119748,2022,A1 Location in patent:Page/Page column 34