1-Bromo-2-methylpropane → HCID 21894750, compound

Temperature

120 °C

The crude 5-bromo-1H-indazole (compound 2f, 100 mmol) was dissolved in 250 mL of DMF. K2CO3 (20.7 g, 150 mmol) and 1-bromo-2-methylpropane (16.3 mL, 150 mmol) were added. The mixture was heated to 120° C. under nitrogen atmosphere for 16 hours. The mixture was cooled to room temperature and concentrated under reduced pressure. Water (200 mL) and CH2Cl2 (200 mL) were added to the residue and stirred vigorously for 30 minutes. The layers were separated and the aqueous layer was extracted with CH2Cl2. The combined extracts were dried over anhydrous MgSO4, filtered through Celite, and concentrated under reduced pressure to provide about 30 g of crude material. The crude material was purified by chromatography (1:9 to 1:4 ether/hexanes) to provide 12.870 g of compound 3f as a dark red oil, yielding 50.8% for steps A and B. MS ESI (+) m/z 253 and 255 (M+1) detected. 1H-NMR (400 MHz, CDCl3) δ 7.93 (s, 1H), 7.87 (m, 1H), 7.43 (m, 1H), 7.29 (m, 1H), 7.29 (m, 1H), 4.15 (m, 2H), 2.33 (m, 1H), 0.92 (m, 6H).

1. temperatureThe mixture was cooled to room temperature
2. concentrationconcentrated under reduced pressure
3. additionWater (200 mL) and CH2Cl2 (200 mL) were added to the residue
4. customThe layers were separated
5. extractionthe aqueous layer was extracted with CH2Cl2
6. dry with materialThe combined extracts were dried over anhydrous MgSO4
7. filtrationfiltered through Celite
8. concentrationconcentrated under reduced pressure
9. customto provide about 30 g of crude material
10. customThe crude material was purified by chromatography (1:9 to 1:4 ether/hexanes)

ORD record

ord-54210222d1ef44aa90b61133896e3743

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08518983B2