In a 1000 mL round bottom flask, n-hexadecyl bromide (97.5 g, 0.32 mol, 1 eq.), 1,3-propanediol (73.5 g, 0.96 mol, 3 eq.), DMSO (200 mL), DMF (200 mL), and potassium hydroxide (72 g, 1.28 mol, 4 eq.) were added in turn and the reaction was stirred for 16 h at room temperature. Upon completion of the reaction, 500 mL of water was added to the reaction mixture and the pH was adjusted to neutral with 5 M hydrochloric acid solution, followed by extraction with ethyl acetate (500 mL x 2). The organic phases were combined and washed with saturated saline (500 mL x 2). The organic layer was collected, dried over anhydrous sodium sulfate (10 g), filtered and the filtrate concentrated under reduced pressure to give 102 g of yellow solid. Crystallization by petroleum ether gave 85 g of white flaky crystals in 88.4% yield.
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