反应详情

To a stirred solution of tert-butyl 4-amino-3-methoxyphenylacetate (1.11 g, 4.68 mmol) and Et3N (720 ml, 5.17 mmol) in THF (10 ml) was added 2-trifluoromethylphenyl isocyanate (707 ml, 4.68 mmol) and the reaction mixture was stirred at room temperature for 2 days. The reaction mixture was concentrated to a small volume and diluted with n-hexane. Resulting precipitate was collected under a reduced pressure and washed with n-hexane to give tert-butyl 3-methoxy-4-[N′-(2-trifluoromethylphenyl)ureido]phenylacetate (1.11 g, 56%) as a white crystalline powder. mp 131–133° C.; 1H-NMR (CDCl3) δ 1.44 (s, 9 H), 3.49 (s, 2 H), 3.85 (s, 3 H), 6.83–6.88 (m, 3 H), 6.98 (br s, 1 H), 7.17–7.21 (m, 1 H), 7.52–7.59 (m, 2 H), 7.89–7.91 (m, 1 H), 8.04–8.06 (m, 1 H).

1. concentrationThe reaction mixture was concentrated to a small volume
2. additiondiluted with n-hexane
3. customResulting precipitate
4. customwas collected under a reduced pressure
5. washwashed with n-hexane