p-Toluenesulfonic acid monohydrate → Methyl 3-(oxazol-2-yl)-3-(4-(tetrahydro-2H-pyran-2-yloxy)phenyl)acrylate
Reaction equation
[O:1]1[CH:5]=[CH:4][N:3]=[C:2]1[CH:6]([C:12]1[CH:17]=[CH:16][C:15]([O:18][CH:19]2[CH2:24][CH2:23][CH2:22][CH2:21][O:20]2)=[CH:14][CH:13]=1)[CH2:7][C:8]([O:10][CH3:11])=[O:9].O.C1(C)C=CC(S(O)(=O)=O)=CC=1>CO>[O:1]1[CH:5]=[CH:4][N:3]=[C:2]1[C:6]([C:12]1[CH:17]=[CH:16][C:15]([O:18][CH:19]2[CH2:24][CH2:23][CH2:22][CH2:21][O:20]2)=[CH:14][CH:13]=1)=[CH:7][C:8]([O:10][CH3:11])=[O:9]Participants
4
Procedure
A mixture of compound 10.4 (2.1 mmol), p-toluenesulfonic acid monohydrate (0.57 mmol) in MeOH (15 mL) was stirred at room temperature for 1.5 hours. After quenching with saturated aqueous NaHCO3, MeOH was removed under reduced pressure. The residue was extracted with EtOAc, and the combined organic extracts were washed with saturated brine, dried over anhydrous sodium sulfate, and filtered through short plug of silica gel. Upon concentration, compound 10.3 was obtained. MS ESI (pos.) m/e 248.1 (M+1). 1H NMR (500 MHz) (DMSO-d6) δ 9.04 (s, 1H); 7.99 (s, 1H); 7.14 (s, 1H); 7.05(m, 2H); 6.72 (m, 2H); 4.49-4.52 (m, 1H); 3.57 (s, 1H); 3.22-3.27(m, 1H); 2.89-2.94(m, 1H).