Lithium borohydride → HCID 71116157, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 3-{[4-(methyloxy)phenyl]methyl}-2-oxo-7-{[(phenylmethyl)oxy]methyl}-1-oxa-3-azaspiro[4.5]decane-7-carboxylate (6.523 g, 14.38 mmol) in THF (27.9 mL) under nitrogen at −78° C. was added lithium aluminium hydride (1M in THF, 71.9 mL, 71.9 mmol) over 10 minutes and stirred for 2 days. The reaction was then quenched slowly with water (5 mL), followed by the addition of 2N HCl (200 mL). The reaction mixture was then extracted with EtOAc (2×150 mL). The combined organic layers were dried over Na2SO4, filtered, and concentrated. To the solution in THF (27.9 mL) was added lithium borohydride (2N in THF, 10.79 mL, 21.57 mmol) and the mixture was stirred for 30 minutes, then heated at 50° C. The additional lithium borohydride (2N in THF, 3.6 mL, 7.19 mmol) was added. The reaction mixture was then cooled to RT and quenched slowly with 2N HCl (100 mL). The mixture was then extracted with EtOAc (2×100 mL) and the combined organic layers were dried over Na2SO4, filtered, and concentrated. The mixture was then loaded onto florisil and purified using silica gel chromatography CISCO): 10-80% ethyl acetate/hexanes (30 min), 80% (5 min), 80 g silica. The product eluted at 26 minutes to yield 7-(Hydroxymethyl)-3-{[4-(methyloxy)phenyl]methyl}-7-{[(phenylmethyl)oxy]methyl}-1-oxa-3-azaspiro[4.5]decan-2-one as a colorless oil (5.2 g, 81% yield). MS (m/z) 426.1 (M+H+).

Provenance & Evidence