Potassium Carbonate → HCID 86680008, compound

A mixture of 4-nitropyrazole (1.13 g, 10 mmol) and K2CO3 (3.4 g, 25 mmol) in MeCN (50 mL) was stirred at room temperature for 15 min prior to addition of 3-(bromomethyl)-3-methyloxetane (1.8 g, 11 mmol). The reaction mixture was stirred at room temperature for 18 hr, filtered and the filter cake washed with MeCN. The filtrate was concentrated under reduced pressure and the residue purified by silica gel column chromatography (0-100% EtOAc/isohexane) gradient to afford 1-((3-methyloxetan-3-yl)methyl)-4-nitro-1H-pyrazole as a colorless solid (1.43 g, 73%). A portion of this solid (206 mg, 1.04 mmol) dissolved in MeOH (20 mL) was treated with ammonium formate (260 mg, 4.13 mmol) and 10% palladium on carbon (50 mg). The mixture was heated at 80° C. for 1.5 hr, cooled, filtered through Celite® and the filtrate concentrated under reduced pressure to afford 1-((3-methyloxetan-3-yl)methyl)-1H-pyrazol-4-amine as a pale pink gum (160 mg, 92%). 1H NMR (400 MHz, CDCl3) δ 7.15 (s, 1H), 6.97 (s, 1H), 4.66 (d, J=6.1 Hz, 2H), 4.37 (d, J=6.1 Hz, 2H), 4.19 (s, 2H), 2.91 (s, 2H), 1.23 (s, 3H).

1. stirringThe reaction mixture was stirred at room temperature for 18 hr
2. filtrationfiltered
3. washthe filter cake washed with MeCN
4. concentrationThe filtrate was concentrated under reduced pressure
5. customthe residue purified by silica gel column chromatography (0-100% EtOAc/isohexane) gradient

ORD record

ord-b86bc8dfaa4646d889734ef5b1d80a6b

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08614206B2