[Cl:1][C:2]1[CH:9]=[C:8]([O:10][CH3:11])[C:5]([CH:6]=O)=[C:4]([OH:12])[CH:3]=1.CN(C)C=O.C(=O)([O-])[O-].[Cs+].[Cs+].Cl[CH2:25][C:26](=[O:28])[CH3:27]>>[Cl:1][C:2]1[CH:9]=[C:8]([O:10][CH3:11])[C:5]2[CH:6]=[C:25]([C:26](=[O:28])[CH3:27])[O:12][C:4]=2[CH:3]=1A stirred solution of 4-chloro-2-hydroxy-6-methoxybenzaldehyde (Example 37B, 1.79 g, 9.59 mmol) in N,N-dimethylformamide (15 mL, 9.59 mmol) was charged with cesium carbonate (3.75 g, 11.51 mmol) and 1-chloropropan-2-one (0.975 mL, 11.51 mmol). The reaction mixture was heated in a sealable vessel at 65° C. for 7 hours, was filtered over a Whatman filter paper to remove insolubles rinsing with DCM then washed with sat. NaHCO3. The organic phase was dried (MgSO4), filtered and concentrated to dryness. The residue was purified by ISCO using hexanes/EtOAc as eluent. Fractions containing the desired product were concentrated to give the title material (1.43 g, 6.37 mmol, 66% yield) as a light yellow solid. LC (Method A): 1.952 min. LCMS (APCI) calcd for C11H10ClO3 [M+H]+ m/z 225.03, found 225.0. 1H NMR (CDCl3, 400 MHz) δ ppm: 7.94 (d, J=0.8 Hz, 1H), 7.49 (dd, J=0.8, 1.6 Hz, 1H), 6.97 (d, J=1.6 Hz, 1H), 3.97 (s, 3H).
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