To a stirred solution of methyl 1-hydroxy-3,6,9,12,15,18,21,24,27,30,33,36-dodecaoxanonatriacontan-39-oate (265a) (1.2 g, 1.897 mmol) in dichloromethane (9.48 mL) at 0° C. was added triethylamine (0.529 mL, 3.79 mmol), toluene sulfonylchloride (0.542 g, 2.84 mmol) and DMAP (0.023 g, 0.190 mmol). The mixture was stirred for one hour at 0° C. and then three hours at ambient temperature, after which it was quenched with water and extracted twice with dichloromethane. The organic extracts were washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. Purification by silica gel chromatography (5% MeOH/CH2Cl2) gave methyl 1-(tosyloxy)-3,6,9,12,15,18,21,24,27,30,33,36-dodecaoxanonatriacontan-39-oate (265b) (1.0 g, 67%) as a light yellow oil. 1H NMR (400 Hz, CDCl3): δ 7.80 (d, J=8.4 Hz, 2H), 7.35 (d, J=8.0 Hz, 2H), 4.16 (t, J=4.8 Hz, 2H), 3.75 (t, J=6.4 Hz, 2H), 3.69 (s, 3H), 3.64 (m, 46H), 2.60 (t, J=6.4 Hz, 2H), 2.45 (s, 3H).
