2,3-Dimethyl-2H-indazole-6-boronic acid pinacol ester synthesis

5synthesis methods

Product Name:2,3-Dimethyl-2H-indazole-6-boronic acid pinacol ester
CAS Number:1300582-62-0
Molecular formula:C15H21BN2O2
Molecular Weight:272.15

1142189-49-8
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$130.00/250mg

73183-34-3
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$6.00/5g

2,3-Dimethyl-2H-indazole-6-boronic acid pinacol ester

1300582-62-0
11 suppliers
$1065.00/100mg

Yield:1300582-62-0 83%

Reaction Conditions:

with potassium acetate;dichloro(1,1'-bis(diphenylphosphanyl)ferrocene)palladium(II)*CH₂Cl₂ in 1,4-dioxane at 80; for 12.5 h;Inert atmosphere;

Steps:

116

Intermediate 116 2,3-dimethyl-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2H-indazole To a solution of intermediate 114b (0.80 g, 3.55 mmoles) in Dioxan (14 ml), bis(pinacaloto)diboron (0.992 g, 3.90 mmoles) and potassium acetate (0.697 g, 7.10 mmoles) were added and the system is degassed for 30 min. Bis(diphenylphosphinoferrocene)dichloro palladium.CH₂Cl₂(0.145 g, 0.177 mmoles) was added under nitrogen atmosphere and heated to 80° C. After 12 h, the reaction mixture filtered through celite and concentrated. The crude product was purified by column chromatography with ethyl acetate:petroleum ether to afford the title compound as off-white solid (0.80 g, 83% yield).). ¹H-NMR (δ ppm, DMSO-d₆, 400 MHz): δ 7.85 (s, 1H), 7.62 (dd, J=8.3, 0.8 Hz, 1H), 7.19 (d, J=8.4 Hz, 1H), 4.05 (s, 3H), 2.58 (s, 3H), 1.29 (s, 12H).

References:

US2011/118257,2011,A1 Location in patent:Page/Page column 100