Ethyl Acetate → 1,7-Diazaspiro[4.4]nonane-1-carboxylic acid, 7-[3-(1-methylethoxy)-4-nitrophenyl]-, 1,1-dimethylethyl ester

Participants

Reaction Steps

A mixture of 3.0 g of tert-butyl 1,7-diazaspiro[4.4]nonane-1-carboxylate and 2.64 g of 4-fluoro-1-nitro-2-(propan-2-yloxy)benzene (obtained according to method 6), and 2.75 g of potassium carbonate in DMSO is stirred at ambient temperature overnight. The mixture is taken up with ethyl acetate and washed twice with 10 volumes of water. The organic phase is dried over magnesium sulfate and concentrated under vacuum. The crude product is purified on 120 g of silica, elution being carried out with dichloromethane, so as to obtain 3.40 g of 2-methylpropan-2-yl 7-[4-nitro-3-(propan-2-yloxy)phenyl]-1,7-diazaspiro[4.4]nonane-1-carboxylate in the form of a dark yellow solid.

Provenance & Evidence