[CH2:1]([O:8][C:9]1[C:10]([CH:18]=[O:19])=[CH:11][C:12]2[O:16][CH2:15][CH2:14][C:13]=2[CH:17]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[H-].C([Al+]CC(C)C)C(C)C.Cl>C1(C)C=CC=CC=1>[CH2:1]([O:8][C:9]1[C:10]([CH2:18][OH:19])=[CH:11][C:12]2[O:16][CH2:15][CH2:14][C:13]=2[CH:17]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1A flamed dried, N2 purged 1-liter, 3-neck flask equipped with a dropping funnel mechanical stirrer, and thermometer was charged with 5-benzyloxy-2,3-dihydrobenzofuran-6-carboxaldehyde (30.00 g, 0.12 moles) and anhydrous toluene (150 ml). The resultant yellow solution was cooled to -65° C. and with efficient stirring a diisobutylaluminum hydride solution in toluene (77 ml of a 25 wt. %) was added dropwise over 30 minutes. Upon complete addition, the reaction mixture was allowed to warm to room temperature and stirred 1 hour more. The reaction mixture was poured slowly into 2N HCl (300 ml) and crushed ice (400 ml) with rapid stirring. The quenched mixture was extracted sequentially with Et2O (2×300 ml) and EtoAC (2×200 ml). The combined organic layers were washed with brine (2×300 ml), dried over MgSO4, filtered, and the filtrate concentrated in vacuo to afford 5-benzyloxy-6-hydroxymethyl-2,3-dihydobenzofuran as a white precipitate (30.0 g, 97.5%).
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