Trifluoroacetic acid → HCID 10466657, compound

Participants

Reaction Conditions

Reaction Steps

To the N′-(4-tert-butyl-cyclohexyl)-hydrazinecarboxylic acid tert-butyl ester (7.61 g) in CH2Cl2 (30 mL) was added TFA (10 mL). After 5 h at RT, the solvent was removed under reduced pressure. The residue was dissolved in glacial acetic acid (100 mL), methyl acetoacetate (4.46 g, 38.4 mmol) was added and the reaction was heated to 100° C. for 18 h. After allowing the reaction to cool to RT, the solvent was removed under reduced pressure. Flash chromatography of the residue (50% to 80% EtOAc/hexanes, silica gel) gave the two isomers of 2-(4-tert-butyl-cyclohexyl)-5-methyl-2,4-dihydro-pyrazol-3-one as pale yellow oils. Isomer 1: 2.67 g; TLC Rf 0.30 (silica gel, 1:1 EtOAc/hexanes); MS (ES+) m/z 237.0 (M+H+). Isomer 2: 0.66 g; TLC Rf 0.15 (silica gel, 1:1 EtOAc/hexanes); MS (ES+) m/z 237.4 (M+H+).

Provenance & Evidence