Methanol → (1aR,5aR)-2-(6-methoxypyridazin-3-yl)-1a,2,5,5a-tetrahydro-1H-2,3-diaza-cyclopropa[a]pentalene-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of (1aR,5aR)-2-(6-chloropyridazin-3-yl)-1a,2,5,5a-tetrahydro-1H-2,3-diaza-cyclopropa[a]pentalene-4-carboxylic acid ethyl ester (245 mg, 0.804 mmol) in methanol (2 mL) and THF (2 mL) was added a 2.0 M aqueous solution of sodium hydroxide (1.206 mL, 2.412 mmol). The reaction was stirred at 23° C. for 4 h. The organic solvents were removed by distillation. To the remaining residue was added 15 mL water. The aqueous solution was acidified to pH 2 by addition of 1 M HCl. The resulting precipitate was collected by filtration, rinsed with water, then dried to provide a 4:1 mixture (based on LC) of (1aR,5aR)-2-(6-chloropyridazin-3-yl)-1a,2,5,5a-tetrahydro-1H-2,3-diaza-cyclopropa[a]pentalene-4-carboxylic acid and (1aR,5aR)-2-(6-methoxypyridazin-3-yl)-1a,2,5,5a-tetrahydro-1H-2,3-diaza-cyclopropa[a]pentalene-4-carboxylic acid (180 mg) which was used without further purification. LCMS m/z=273.3 [M+H]+ and 277.2 [M+H]+.

Provenance & Evidence