Hydrochloric Acid → HCID 67061081, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of bicyclo[3.1.0]hexan-3-one (0.30 g, 3.12 mmol) and diethyl oxalate (0.433 mL, 3.20 mmol) in denatured absolute ethanol (10 mL) was added a 1.0 M THF solution of potassium tert-butoxide (3.28 mL, 3.28 mmol). The resulting yellow solution was stirred at 20° C. for 2 h. (2,4-Difluorophenyl)hydrazine hydrochloride (0.564 g, 3.12 mmol) was added followed by a 3.0 M aqueous solution of hydrogen chloride (3.12 mL, 9.36 mmol). The reaction was stirred at 40° C., for 18 h. Brine (100 mL) was added. The mixture was extracted with dichloromethane (3×25 mL). The combined organic extracts were dried over MgSO4, filtered, then concentrated under reduced pressure. The residue was purified by silica gel flash chromatography to give a mixture of the title compound (0.672 g) and 1-(2,4-difluoro-phenyl)-3b,4,4a,5-tetrahydro-1H-cyclopropa[3,4]cyclopenta[1,2-c]pyrazole-3-carboxylic acid methyl ester (0.090 g) as yellow solids. LCMS m/z=305.3 [M+H]+; 1H NMR (400 MHz, CDCl3) δ ppm 0.36 (td, J=4.5, 3.8 Hz, 1H), 1.17 (td, J=7.9, 5.0 Hz, 1H), 1.41 (t, J=7.2 Hz, 3H), 2.09-2.16 (m, 1H), 2.33-2.37 (m, 1H), 2.80 (d, J=16.9 Hz, 1H), 2.98 (dd, J=16.9, 6.7 Hz, 1H), 4.36-4.49 (m, 2H), 6.92-6.99 (m, 2H), 7.61-7.67 (m, 1H).

Provenance & Evidence