[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[CH:8]=[C:7]([C:12]([N+:17]([O-:19])=[O:18])([CH2:15][OH:16])[CH2:13][OH:14])[CH:6]=[CH:5]2.C(Cl)Cl.CO[C:25](OC)([CH3:27])[CH3:26].B(F)(F)F>CCOC(C)=O.CCCCCC>[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[CH:8]=[C:7]([C:12]1([N+:17]([O-:19])=[O:18])[CH2:15][O:16][C:25]([CH3:27])([CH3:26])[O:14][CH2:13]1)[CH:6]=[CH:5]2
2-(6-Bromo-naphthalen-2-yl)-2-nitro-propane-1,3-diol (32.6 g, 0.100 mol) was dissolved in methylene chloride (150 mL, 2.3 mol; Acros, anhydrous) and 2,2-dimethoxypropane (180 mL, 1.5 mol; Aldrich), cooled with an ice bath. Boron trifluoride is etherate (10.1 mL, 0.0800 mol; Aldrich) was added slowly. The mixture was stirred for 15 min and large amount of solid precipitated. The cooling bath was removed and the mixture was stirred at r.t. for 4 hours. The mixture was quenched with aqueous saturated NaHCO3 (˜600 mL) to pH˜8, extracted with EtOAc (600 mL, 300 mL, 2×100 mL). The EtOAc layer was washed with water, brine, dried over Na2SO4, filtered. The solvent was evaporated to 100 mL. The resulted solid product was collected by filtration and the mother liquid was concentrated further to afford the second crop of product. Rf of product=0.4 (EtOAc/hexane=1/4). Total product weighed 30.0 g (yield 82%).
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