[N+:1]([C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=1O)([O-:3])=[O:2].[CH3:11][O:12][C:13](=[O:21])[C:14]([CH3:20])([CH3:19])[CH2:15][CH2:16][CH2:17]Br.C(=O)([O-])[O-:23].[K+].[K+]>C(#N)C>[CH3:19][C:14]([CH3:20])([CH2:15][CH2:16][CH2:17][O:23][C:6]1[CH:7]=[CH:8][CH:9]=[C:4]([N+:1]([O-:3])=[O:2])[CH:5]=1)[C:13]([O:12][CH3:11])=[O:21]A mixture of 27.8 g (200 mmol) of 2-nitrophenol, 44.6 g (200 mmol) of methyl-5-bromo-2,2-dimethylpentanoate (Journal of Medicinal Chemistry, Vol. 26, pp 1020-1027 (1983)) and 30.5 g (220 mmol) of anhydrous potassium carbonate in 300 ml of acetonitrile is stirred at reflux for 18 hours. The inorganic salts are removed, washed with acetonitrile and the filtrate is concentrated on a rotary evaporator. The residue is taken up in diethyl ether and the solution washed with 2N potassium hydroxide (3×50 ml), brine, dried (magnesium sulfate), and evaporated to afford 55.9 g of crude product. Distillation gives 52.9 g of 2,2-dimethyl-5-(3-nitrophenoxy)pentanoic acid, methyl ester, bp 160°-165° C. (0.5 mm).
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