CC(C)([O-])C.[K+].[N+]([C:10]1[CH:15]=[CH:14][CH:13]=[C:12]([N+:16]([O-:18])=[O:17])[CH:11]=1)([O-])=O.[CH2:19]([OH:27])[CH2:20][C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1.CN(C)P(N(C)C)(N(C)C)=O>O>[C:21]1([CH2:20][CH2:19][O:27][C:10]2[CH:11]=[C:12]([N+:16]([O-:18])=[O:17])[CH:13]=[CH:14][CH:15]=2)[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1Potassium t-butoxide (11.2 g; 0.1 mol) is added under a nitrogen atmosphere to a stirred mixture of m-dinitrobenzene (16.8 g; 0.1 mol), phenethyl alcohol (12.2 g; 0.1 mol) and hexamethylphosphoramide (HMPA; 200 ml). Almost instantly a dark red color develops and then slowly fades in the course of the reaction and turns black. The reaction mixture is stirred for 7 days at room temperature. It is then drowned in water, and extracted twice with methylene chloride (500 ml). The methylene chloride solution is washed with water (3X), saturated brine (1X), dried over magnesium sulfate and evaporated to yield 53.5 g of a dark oil. Additional solvent (HMPA) and some m-dinitrobenzene is removed from the oil by heating same at about 90° C. under 0.5 mm vacuum. The residual oil (~25 g) is chromatographed on 1 kg silica gel with 3:1 hexane:methylene chloride. Collected fractions, containing the same material by thin layer chromatography, are combined and evaporated to afford 7.4 g (30%) of product, a light yellow oil. On standing, the oil crystallizes, mp. 46.5°-49° C.
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