1-(2-Tetrahydropyranyl)-1H-pyrazole-4-boronic acid pinacol ester synthesis
- Product Name:1-(2-Tetrahydropyranyl)-1H-pyrazole-4-boronic acid pinacol ester
- CAS Number:1003846-21-6
- Molecular formula:C14H23BN2O3
- Molecular Weight:278.15
110-87-2
518 suppliers
$10.00/1g
269410-08-4
383 suppliers
$5.00/1g
1003846-21-6
134 suppliers
$6.00/250mg
Yield:1003846-21-6 94%
Reaction Conditions:
with trifluoroacetic acid in toluene at 90; for 2 h;
Steps:
8.1 Step 1. Synthesis of 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (C17)
3,4-Dihydro-2H-pyran (5.6 g, 67 mmol) and trifluoroacetic acid (1.17 g, 10.3 mmol) were added to a solution of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H- pyrazole (10.0 g, 51.5 mmol) in toluene (200 mL), and the reaction mixture was heated to 90 °C for 2 hours. After cooling to room temperature, the reaction mixture was partitioned between ethyl acetate (200 mL) and saturated aqueous sodium bicarbonatesolution (100 mL), and the aqueous layer was extracted with ethyl acetate (100 mL). The combined organic layers were washed with saturated aqueous sodium chloride solution (100 mL), dried over sodium sulfate, filtered, and concentrated in vacuo. Silica gel chromatography (Gradient: 10% to 50% ethyl acetate in petroleum ether) provided the product as a white solid. Yield: 13.4 g, 48.2 mmol, 94%. 1H NMR (400 MHz, CDCl3) 7.94 (s, 1H), 7.83 (s, 1H), 5.41 (dd, J=9.5, 2.5 Hz, 1H), 4.01-4.08 (m, 1H), 3.65-3.74(m, 1H), 1.98-2.18 (m, 3H), 1.6-1.76 (m, 3H), 1.32 (s, 12H).
References:
PFIZER INC.;GALATSIS, Paul;HAYWARD, Matthew Merrill;HENDERSON, Jaclyn;KORMOS, Bethany Lyn;KURUMBAIL, Ravi G;STEPAN, Antonia Friederike;VERHOEST, Patrick Robert;WAGER, Travis T.;ZHANG, Lei WO2014/1973, 2014, A1 Location in patent:Page/Page column 60; 61; 62
1040377-02-3
42 suppliers
$64.00/100mg
73183-34-3
557 suppliers
$6.00/5g
1003846-21-6
134 suppliers
$6.00/250mg
110-87-2
518 suppliers
$10.00/1g
1003846-21-6
134 suppliers
$6.00/250mg
73183-34-3
557 suppliers
$6.00/5g
1003846-21-6
134 suppliers
$6.00/250mg