Acetone → HCID 69245759, compound

Participants

Reaction Steps

To a stirred solution of rac-(4R,5S,6S)-1-benzyloxy-5,6-dihydroxy-1-azaspiro[3.5]nona-8-ene-2,7-dione (2) (109 mg, 0.377 mmol) and 2,2-dimethoxypropane (0.24 ml, 1.885 mmol) in dry acetone (0.75 ml) was added at room temperature catalytic amount of p-TsOH (1% mmol). The resulting mixture was stirred at room temperature for 18 h, then quenched with saturated aqueous Na2CO3 solution (1 ml) and extracted with AcOEt (3×2 ml). The combined organic extracts were washed with brine (3 ml), dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane-AcOEt, 5:2) to give rac-(4R,5S,6S)-1-benzyloxy-5,6-dimethylmethylendioxy-1-azaspiro[3.5]nona-8-ene-2,7-dione (13) as a solid (52 mg, 42%).

Provenance & Evidence