Acetic acid--water (1/1) → 7-Oxaspiro[3.5]nonan-2-one

Reaktionsgleichung

Cl[C:2]1(Cl)[C:5]2([CH2:10][CH2:9][O:8][CH2:7][CH2:6]2)[CH2:4][C:3]1=[O:11].C(O)(=O)C.O>CCOCC.[Zn]>[CH2:4]1[C:5]2([CH2:10][CH2:9][O:8][CH2:7][CH2:6]2)[CH2:2][C:3]1=[O:11]

Komponenten

Versuchsvorschrift

The impure 1,1-dichloro-7-oxaspiro[3.5]nonan-2-one from Step B was stirred with zinc (150 mg; 2.30 mmol) and 5 mL of acetic acid/water (1:1) for 4 hours. The mixture was stored at −20° C. for 1 day, diluted with ether (20 mL) and filtered through a pad of Celite®. The solution was neutralized with aqueous sodium bicarbonate solution and extracted into ether (5×20 mL). The combined ether extracts were dried (sodium sulfate), filtered and concentrated under reduced pressure. The material was purified by chromatography on silica gel, eluting with 1:1 ethyl acetate/hexane to give the product as a colorless oil (61 mg).