Sodium hydride → (R)-Methyl 2-(((2-((tert-butoxycarbonyl)amino)pent-4-en-1-yl)oxy)methyl)benzoate

A solution of compound 18g (6.2 g, 30.8 mmol) and compound 18c (8.5 g, 36.9 mmol) in THF (30 mL) was cooled in an ice bath under argon. To this mixture was added NaH (2.5 g, 61.6 mmol, 60% wt in oil) portionwise. The ice bath was removed and the reaction mixture was allowed to stir at rt for 2 h and then quenched with MeOH (10 mL). The mixture was concentrated under reduced pressure and the residue was purified by CC to give the desired compound 18h (4.2 g, 39% yield) as a yellow oil. LCMS (m/z): 350.2 (MH+).