[CH2:1](O)[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH3:18].[CH:20](N(C(C)C)CC)(C)C.FC(F)(F)S(OS(C(F)(F)F)(=O)=O)(=O)=O.[C:44]1([C:50]2[CH:51]=[CH:52][C:53]3[O:57][CH:56]=[N:55][C:54]=3[CH:58]=2)[CH:49]=[CH:48][CH:47]=[CH:46][CH:45]=1>C(Cl)(Cl)Cl>[CH2:20]=[C:56]1[N:55]([CH2:1][CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH3:18])[C:54]2[CH:58]=[C:50]([C:44]3[CH:45]=[CH:46][CH:47]=[CH:48][CH:49]=3)[CH:51]=[CH:52][C:53]=2[O:57]1Powdered 1-octadecanol (15.4 g, 56.9 mmol) and diisopropylethylamine (9.9 mL, 56.9 mmol) are dissolved in 200 mL CHCl3 (dried over molecular sieves). To the above stirred solution is added trifluoromethanesulfonic anhydride (10.4 mL) dropwise over a period of 1 hours. Powdered 5-phenylbenzoxazole (16.7 g, 79.7 mmol) is then added portion-wise over a period of 10 minutes. After stirring overnight, the solution is washed with water and dried with anhydrous Na2SO4. The solution is loaded onto a large silica column and eluted with MeOH/CHCl3. The product is obtained as a colorless solid (20 g, 77%).
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