Acetic Anhydride → HCID 69220169, compound

Reaction equation

[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([NH2:9])=[CH:5][C:4]=1[O:10][CH2:11][O:12][CH2:13][CH2:14][Si:15]([CH3:18])([CH3:17])[CH3:16].[C:19](OC(=O)C)(=[O:21])[CH3:20]>CN(C)C1C=CN=CC=1.ClC(Cl)C>[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([NH:9][C:19](=[O:21])[CH3:20])=[CH:5][C:4]=1[O:10][CH2:11][O:12][CH2:13][CH2:14][Si:15]([CH3:17])([CH3:16])[CH3:18]

Participants

Procedure

A mixture of Example 476B, acetic anhydride (20 mL), and 4-(dimethylamino)pyridine (722 mg, 5.9 mmol) in dichloroethane (150 mL) was stirred at room temperature for 2 hours. The reaction mixture was then concentrated under vacuum, diluted with ethyl acetate, washed with water and brine, dried (MgSO4), filtered, and concentrated under vacuum. The residue was diluted with hexanes and stirred vigorously until a solid formed. The solid was filtered, rinsed with hexane, and dried under vacuum to produce 15 g (81% over 3 steps from Examples 476A-C) of the desired product. MS (ESI) m/e 334 (M+Na)+; 1H NMR (300 MHz, DMSO-d6) □ 9.74 (s, 1H), 7.33 (d, J=2.7 Hz, 1H), 7.18 (dd, J=2.5, 8.7 Hz, 1H), 6.89 (d, J=8.8 Hz, 1H), 5.13 (s, 2H), 3.67-3.73 (m, 2H), 3.71 (s, 3H), 1.98 (s, 3H), 0.86-0.92 (m, 2H), -0.02 (s, 9H).