446292-08-6

1H-isoindole-1,3(2H)-dione, 2-[[(5S)-2-oxo-3-[4-(3-oxo-4-morpholinyl)phenyl]-5-oxazolidinyl]methyl]- is an important intermediate for the synthesis of rivaroxaban, which is an anticoagulant and the first orally active direct factor Xa inhibitor.

1325210-64-7

161596-47-0

446292-08-6

The general procedure for the synthesis of 2-[[(5S)-2-oxo-3-[4-(3-oxo-4-morpholinyl)phenyl]-5-oxazolidinyl]methyl]-1H-isoindole-1,3(2H)-dione from 4-(3-oxomorpholinyl)phenyl isocyanate and (S)-2-(ethoxylen-2-ylmethyl)isoindoline-1,3-dione was as follows: the (S)- 2-(oxiran-2-ylmethyl)isoindoline-1,3-dione (4.56 g, 22.46 mmol, 1.3 eq.) and 4-(4-isocyanatophenyl)morpholin-3-one (3.77 g, 17.29 mmol) were dissolved in isoamyl acetate (70 mL), respectively. The reaction mixture was heated to 120 °C, followed by the addition of magnesium chloride (0.12 g, 1.28 mmol). After the reaction lasted for 4 h, a white solid product (6.97 g, 95.5% yield) was obtained by filtration. The product was confirmed by mass spectrometry by ESI-MS (m/z): 422 (M + H), 444 (M + Na); 1H NMR (400 MHz, CDCl3) δ: 3.74 (m, 2H), 3.94 (m, 4H), 4.10 (m, 2H), 4.32 (s, 2H), 4.98 (m, 1H), 7.34 (d, 2H), and 7.56 (d, 2H), 7.75 (m, 2H), 7.88 (m, 2H) were characterized by NMR; HPLC purity was 98.82%.