Hydrochloric Acid → HCID 67044653, compound

Participants

Reaction Steps

Methyl 2-{[4-amino-3-({[(1,1-dimethylethyl)oxy]carbonyl}amino)phenyl]carbonyl}benzoate (0.217 g, 0.586 mmol) was dissolved in tetrahydrofuran (3 mL) and cooled in an ice bath. Sodium hydride (60 wt. % dispersion in oil; 0.024 g, 0.600 mmol) was added followed by dropwise addition of iodomethane (0.037 mL, 0.594 mmol). The mixture was stirred for 1.1 h and then iodomethane (0.100 mL, 1.61 mmol) was added dropwise. The mixture was stirred for a further 1 h and then sodium hydride (60 wt. % dispersion in oil; 0.019 g, 0.475 mmol) was added and the mixture was stirred for a further 0.25 h. The mixture was quenched with 1 N hydrochloric acid. The aqueous portion was extracted with ethyl acetate (2×). The combined organic portion was washed with saturated sodium bicarbonate solution. The ethyl acetate portion was dried over sodium sulfate, filtered and concentrated in vacuo to afford a mixture of 4:1 mono-N-methylated: di-N-methylated material (0.115 g). The aqueous portion was acidified with 1 N hydrochloric acid and extracted with ethyl acetate (2×). The organic portion was washed with water, brine, dried over sodium sulfate, filtered and concentrated in vacuo to afford 2-({4-amino-3-[{[(1,1-dimethylethyl)oxy]carbonyl}(methyl)amino]phenyl}carbonyl)benzoic acid as an orange oil which was dissolved in methanol (0.5 mL) and toluene (4.5 mL), cooled in an ice-bath and treated with (trimethylsilyl)diazomethane (2.0M solution in hexanes; 0.200 mL, 0.400 mmol). The mixture was stirred for 0.1 h and then was quenched with 0.5 N hydrochloric acid and partitioned with ethyl acetate. The organic portion was washed with saturated sodium bicarbonate solution, brine, dried over sodium sulfate, filtered and concentrated in vacuo to afford a yellow foam (0.120 g). This yellow foam was combined with the 4:1 mixture of mono- and di-methylated material isolated above (0.115 g) and was purified by column chromatography (ethyl acetate-hexanes 1:1) to afford methyl 2-({4-amino-3-[{[(1,1-dimethylethyl)oxy]carbonyl}(methyl)amino]phenyl}carbonyl)benzoate as a yellow foam (0.167 g, 0.435 mmol, 74% yield). 1H NMR (400 MHz, CDCl3): 8.02 (dd, 1H), 7.65-7.30 (m, 5H), 6.69 (d, 1H), 4.24 (s, 2H), 3.65 (s, 3H), 3.13 (s, 3H), 1.56 (s, 9H); MS (EI) for C21H24N2O5: 407 (MNa+).

Provenance & Evidence