[CH3:1][C:2]1[CH:3]=[CH:4][C:5]([N+:9]([O-:11])=[O:10])=[C:6]([OH:8])[CH:7]=1.[Br:12][CH2:13][CH2:14]Br.C([O-])([O-])=O.[K+].[K+]>CN(C=O)C>[Br:12][CH2:13][CH2:14][O:8][C:6]1[CH:7]=[C:2]([CH3:1])[CH:3]=[CH:4][C:5]=1[N+:9]([O-:11])=[O:10]122.5 g (800 mmol) 5-methyl-2-nitrophenol, 751.0 g (4000 mmol) 1,2-dibromoethane, 110.7 g (800 mmol) K2CO3 were suspended in 400 ml anhydrous DMF. The suspension was heated at 120° C. for 1 hour, then cooled and most of the liquid was evaporated. The residue was dissolved in 1 l CHCl3 and 1 l water. The organic layer was washed with 2×1 l of 1.8% NaOH till the aqueous layer became pale yellow. The organic layer was dried over Na2SO4 for 18 h, filtered and the solvent was evaporated to give ˜240 g oil. The oil was triturated with 240 ml boiling methanol and allowed to settle for 2 h. The resultant precipitate was filtered, washed with 2×100 ml cold methanol and dried at RT for 18 h to afford 89.4 g (43%) off-white crystal. H1NMR (CDCl3) δ (ppm): 2.40(s, 3H), 3.65(t,2H), 4.30(t,2H), 6.85(d,2H), 7.75(d,1H).
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