2,6-Diisopropylphenyl isocyanate → 4-(2,4-Dioxo-1,3-diazaspiro[4.5]dec-1-yl)benzoic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

380 μl (1.85 mmol, 1.2 eq.) of 2,6-diisopropylphenyl isocyanate are added to a solution of 450 mg (1.55 mmol, 1 eq.) of 4-(1-carbamoyl-cyclohexylamino)benzoic acid ethyl ester in 15 ml of toluene. The reaction medium is stirred at 180° C. for 2 hours with microwave irradiation. The toluene is evaporated off and the residue is purified on silica gel (heptane/ethyl acetate). The product 4-(2,4-dioxo-1,3-diazaspiro[4.5]dec-1-yl)benzoic acid ethyl ester is obtained in the form of a white solid.

Provenance & Evidence