A mixture of 2-(4-Bromobenzyl)-2-[4-(diethoxymethyl)benzyl]-1,3-propanediol(3 g, crude), benzyl bromide (3 mL), and NaH (1.2 g, 60% in mineral oil) in 30 mL of DMF was stirred for 14 h at 70° C. The mixture was then quenched with 5 mL of MeOH followed by 50 mL of saturated NH4Cl and extracted with 200 mL of 2:1 hexane/EtOAc. The extract was dried over Na2SO4 and concentrated. The residue was purified by silica gel chromatography eluted with 15:1 hexane EtOAc containing 1% of Et3N to give 2.5 g of the title compound as an oil.
