[CH3:1][C:2]1[NH:3][CH2:4][CH2:5][N:6]=1.C(N(CC)CC)C.Cl.[CH3:15][N:16]([CH2:18][CH2:19][CH2:20][CH2:21][CH2:22][C:23](Cl)=[O:24])[CH3:17]>ClCCl>[CH3:15][N:16]([CH2:18][CH2:19][CH2:20][CH2:21][CH2:22][C:23]([N:6]1[CH2:5][CH2:4][N:3]=[C:2]1[CH3:1])=[O:24])[CH3:17]Dichloromethane (400 mL), 2-methyl-2-imidazoline (56.38 g, 0.637 mol), and triethylamine (283.51 g, 2.802 mol) are placed in a 2000 mL three-necked round bottomed flask equipped with a reflux condenser, internal thermometer, mechanical stirrer, addition funnel, and argon inlet. The solution is brought to reflux and 15 min later a solution of 6-(N,N-Dimethylamino)hexanoyl chloride.hydrochloride (150 g, 0.700 mol), prepared as described in example II, dissolved in dichloromethane (300 mL) is added dropwise over 45 min. The mixture is refluxed for an additional 2 h before being cooled to room temperature. The salts are filtered and washed with methylene chloride. The combined filtrates are washed with 5% NaHCO3 solution (3×300 mL) and water (300 mL). After drying over MgSO4 and filtration, the organic layer is concentrated first by rotary evaporation at 50° C. and then by Kugelrohr distillation at 60°-70° C. (0.2 mm Hg) to give 95.20 g (66%) of an oil which solidifies on standing.
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