Hydrochloric Acid → 5-Benzyloxy-6-hydroxymethyl-2,3-dihydrobenzofuran

Temperature

-65 °C

A 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%).

1. customA flamed dried
2. customN2 purged 1-liter, 3-neck flask
3. customequipped with a dropping funnel mechanical stirrer
4. additionwas added dropwise over 30 minutes
5. additionUpon complete addition
6. temperatureto warm to room temperature
7. extractionThe quenched mixture was extracted sequentially with Et2O (2×300 ml) and EtoAC (2×200 ml)
8. washThe combined organic layers were washed with brine (2×300 ml)
9. dry with materialdried over MgSO4
10. filtrationfiltered
11. concentrationthe filtrate concentrated in vacuo

ORD record

ord-e870ab4ccd4b480db7a7d616ed590c8e

Source dataset

uspto-grants-1987_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04713393