Aluminium lithium hydride → (9aR)-8-(phenylmethyl)octahydropyrazino[2,1-c][1,4]oxazine

Participants

Reaction Conditions

Reaction Steps

To a 0° C. solution of (9aR)-8-(phenylmethyl)hexahydropyrazino[2,1-c][1,4]oxazine-6,7-dione (2.5610 g, 9.84 mmol) in THF (100 mL) was added LiAlH4 (1.12 g, 29.51 mmol) portionwise. The mixture was heated at 70° C. and stirred for 1 week. The mixture was then cooled to 0° C. and quenched by addition of Na2SO4.10H2O (2 g) followed by 1 N aq. NaOH (100 mL). The mixture was extracted with Et2O (2×150 mL), and the combined organic phase was dried over anhydrous Na2SO4, filtered, and concentrated in vacuo. The residue was dissolved in DCM (200 mL), dried over anhydrous Na2SO4, filtered, and concentrated in vacuo. The residue was purified by gradient silica gel chromatography (0% to 100% EtOAc in hexanes; 1% Et3N) to give (9aR)-8-(phenylmethyl)octahydropyrazino[2,1-c][1,4]oxazine (1.8147 g, 79%) as a colorless oil. LCMS: (M+H)+: 233.1.

Provenance & Evidence