Carbonate Ion → Methyl 4-(4-[[(4-[[(tert-butoxy)carbonyl]amino]cyclohexyl)sulfanyl]methyl]-5-methyl-1,3-oxazol-2-yl)benzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Into a 100-mL 3-necked round-bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed A mixture of methyl 4-[5-methyl-4-(sulfanylmethyl)-1,3-oxazol-2-yl]benzoate (3 g, 11.39 mmol, 1.00 equiv), cescium carbonate (5.13 g, 15.70 mmol, 1.39 equiv) and tert-butyl N-[4-(methanesulfonyloxy)cyclohexyl]carbamate (3.22 g, 10.98 mmol, 1.20 equiv) in N,N-dimethylformamide (30 mL) was stirred at 50° C. for 3 h. The reaction was quenched by the addition of 50 mL of water and the resulting solution was extracted with 3×60 mL of ethyl acetate. The organic combined layers was washed with 2×200 mL of brine, dried over anhydrous sodium sulfate and concentrated under vacuum. The residue was purified on\a silica gel column eluted with ethyl acetate/petroleum ether (1:15-1:5). The collected fractions were combined and concentrated under vacuum to give 760 mg (14%) of methyl 4-(4-[[(4-[[(tert-butoxy)carbonyl]amino]cyclohexyl)sulfanyl]methyl]-5-methyl-1,3-oxazol-2-yl)benzoate as a yellow solid. LC-MS: (ES, m/z): 461 [M+H]+, 405, 361, 271, 230, 115.

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