Hexane → 4-(3-Furyl)-7-methylcoumarin

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 3-bromofuran (2.3 g, 16.1 mmol) in dry Et2O (146 ml) was added at -78° C. n-BuLi in hexane (6.42 ml, 16.1 mmol, 2.5M). The resulting solution was stirred for 20 min, then (MeO)3B (1.82 ml, 16.1 mmol) was added dropwise and after 20 min., a mixture of the triflate from Step 1 (4.50 g, 14.6 mmol) and (PPh3)4Pd (1.69 g, 1.46 mmol) in THF (60 ml) and H2O (10 ml) was added. The cooling bath was removed and the resulting mixture was heated to 65° C. for 1.75 h. The solvent was evaporated and H2O was added followed by extraction with EtOAc (3×50 ml). The combined organic phases were washed with brine, dried over MgSO4 and evaporated. Purification by flash chromatography (toluene:(2-10% EtOAc)) gave 2.5 g of the title compound, m.p. 160°-162° C.

Herkunft & Nachweise