Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.
Procedure: Sodium hydride (60% wt in oil) (400 mg, 10 mmol) was added to a stirred solution of tert-butyl 3-hydroxy-2,2-dimethylpropanoate (57) (1.74 g, 10 mmol) in DMF (20 mL) at 0° C., after 30 min a solution of 2,5,8,11,14,17,20-heptaoxadocosan-22-yl methanesulfonate (2.79 g, 6.67 mmol) in DMF (10 mL) was added dropwise, and the reaction mixture was allowed to warm to RT and stirred for 16 h. The reaction was quenched with water (100 mL) and the aqueous layer was extracted with DCM (2×100 mL), the combined organic layers were washed with brine (3×100 mL), dried (MgSO4), filtered and concentrated in vacuo. The crude product was purified by silica gel chromatography (120 g, 0-10% MeOH in EtOAc) to afford tert-butyl 25,25-dimethyl-2,5,8,11,14,17,20,23-octaoxahexacosan-26-oate (58) (1.59 g, 48%) as a colourless oil: 1H NMR (400 MHz, CDCl3) δ: 3.65-3.51 (m, 32H), 3.40 (s, 2H), 3.36 (s, 3H), 1.41 (s, 9H), 1.11 (s, 6H).
was added dropwise
The reaction was quenched with water (100 mL)
the aqueous layer was extracted with DCM (2×100 mL)
the combined organic layers were washed with brine (3×100 mL)
dried (MgSO4)
filtered
concentrated in vacuo
The crude product was purified by silica gel chromatography (120 g, 0-10% MeOH in EtOAc)
Source ID: ord-9880b79475f4415bb167a8ec6b6fe8e2