3,4,5,6-Tetrahydrophthalic anhydride → 3-(3-Bromo-4-fluoro-benzylidene)-4,5,6,7-tetrahydro-3H-isobenzofuran-1-one

Beteiligte Stoffe

Reaktionsschritte

4,5,6,7-tetrahydro-isobenzofuran-1,3-dione (7) (16.7 g, 109.7 mmol) and 3-bromo-4-fluorophenylacetic acid (15.0 g, 64.37 mmol) were heated in the presence of sodium acetate (0.259 g, 3.160 mmol) to 210° C. using a ‘Wood's Alloy’ bath for 4.5 hours. The reaction mixture was then poured into a crucible and cooled to give a crystalline solid. The solid was ground with a mortar and pestle and triturated with ethanol (20 ml). The resultant suspension was then filtered and washed with further ethanol (10 ml). The solid was then dried to afford the desired product as a mixture of geometric isomers. Main peak in LC-MS, (20.78 g, 94% purity) and required no further purification; m/z (LC-MS, ESP), RT=4.74 mins (no ionization observed).

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