2-(2-Methoxy-6-vinylphenoxy)but-3-enyl 4-methylbenzenesulfonate → 8-methoxy-2H-1-benzopyran-2-methanol 4-methylbenzenesulfonate

Beteiligte Stoffe

Reaktionsschritte

A solution of 2-(2-methoxy-6-vinylphenoxy)but-3-enyl 4-methylbenzenesulfonate (4.4 g, 12 mmol) in dichloromethane (100 mL) was treated with benzylidene-bis(tricyclohexylphosphine)dichlororuthenium (0.9 g) at 23° C. with stirring. After 4 hours, the solvent volume was reduced under reduced pressure (to ca. 10 mL) and the solution was pre-adsorbed on silica gel (5 g). Purification by flash chromatography using a solvent gradient of 10 to 20% ethyl acetate in hexane provided 8-methoxy-2H-1-benzopyran-2-methanol 4-methylbenzenesulfonate (4.0 g, 98%) as a dark oil. MS (ESI) m/z 345.0 ([M−H]−).

Herkunft & Nachweise