(3-Trifluoromethylphenyl)urea → HCID 59411352, compound

Participants

Reaction Steps

To a stirred solution of Example 3A (29.3 g, 70.4 mmol) in tetrahydrofuran (450 ml) is given allyl 3-oxobutanoate (10.0 g, 70.4 mmol), N-[3-(trifluoromethyl)phenyl]urea (14.4 g, 70.4 mmol) and polyphosphoric acid ethyl ester (33 mg) [freshly prepared according to the procedure of Cava et al., J. Org. Chem. 34, 2665 (1969)]. The reaction mixture is refluxed for 24 hours after which time the solvent is removed in vacuo, and the residue is purified by column chromatography (silica, eluent: cyclohexane/ethyl acetate mixtures).

Provenance & Evidence