tert-Butyl (2E)-but-2-enoylcarbamate → 1,1-dimethylethyl (3-{[4-(4-methyl-1H-imidazol-1-yl)phenyl]amino}butanoyl)carbamate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 4-(4-methyl-1H-imidazol-1-yl)aniline (for a preparation see Intermediate 104) (500 mg, 2.89 mmol), 1,1-dimethylethyl (2E)-2-butenoylcarbamate (for a preparation see Intermediate 105) (615 mg, 3.32 mmol) and yttrium(III) nitrate hexahydrate (111 mg, 0.289 mmol) in acetonitrile (2 mL) was heated at 50° C. for 15 h. An extra portion of yttrium(III) nitrate hexahydrate (111 mg, 0.289 mmol) was added to the mixture which was stirred for 7 more hours before being cooled to room temperature. Half of the solvent was removed in vacuo and the residue was partitioned between AcOEt (40 mL) and a saturated NaHCO3 aqueous solution (20 mL). The layers were separated and the organic phase was washed with brine (15 mL). The combined aqueous phases were extracted with AcOEt (35 mL) and the combined organic were dried over MgSO4 and concentrated in vacuo. Purification of the residue by flash chromatography on silica gel (gradient: 4 to 8% MeOH in DCM) gave a residue which was further purified by flash chromatography on silica gel (gradient: 60-95% AcOEt in Hexanes) to give 1,1-dimethylethyl (3-{[4-(4-methyl-1H-imidazol-1-yl)phenyl]amino}butanoyl)carbamate (343 mg, 0.956 mmol, 33%) as a colourless sticky solid. LCMS (method A): Retention time 0.94 min, [M+H]+=359.12

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