[CH3:1][C:2]1[CH:7]=[CH:6][C:5]([OH:8])=[CH:4][C:3]=1[N+:9]([O-:11])=[O:10].C([O-])([O-])=O.[K+].[K+].[Br:18][CH2:19][CH2:20][CH2:21]Br>CN(C=O)C.O>[Br:18][CH2:19][CH2:20][CH2:21][O:8][C:5]1[CH:6]=[CH:7][C:2]([CH3:1])=[C:3]([N+:9]([O-:11])=[O:10])[CH:4]=1A solution of 4-methyl-3-nitrophenol (1.00 g, 6.53 mmol) in DMF (6 mL) was treated with K2CO3 (0.903 g, 6.53 mmol) and 1,3-dibromopropane (6.63 mL, 65.3 mmol) and heated to 100° C. for 2.5 h. The cooled mixture was diluted with water and extracted with DCM. The combined organics were dried (MgSO4), filtered and evaporated before purification by column chromatography (SiO2; eluting with 20% EtOAc in cyclohexane) to afford the desired product V-h as a mobile yellow oil (1.05 g, 59%). 1H NMR (300 MHz, CDCl3) δ 7.52 (d, J=2.7 Hz, 1H), 7.23 (d, J=8.5 Hz, 1H), 7.06 (dd, J=8.5, 2.7 Hz, 1H), 4.14 (t, J=5.8 Hz, 2H), 3.60 (t, J=6.4 Hz, 2H), 2.53 (s, 3H), 2.40-2.24 (m, 2H).
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