Dichloromethane → HCID 21841372, Verbindung

Beteiligte Stoffe

Reaktionsschritte

A mixture of 4.85 g of 4-(3-butenyloxy)benzoic acid and 6 ml of thionyl chloride was treated with 3 drops of dimethylformamide and heated to reflux for 3 hrs. The excess acid chloride was thereupon distilled off firstly at normal pressure and then with increasing vacuum, the residue was held under a high vacuum for 2.5 hrs. and subsequently dissolved in 20 ml of methylene chloride. This solution was added dropwise while cooling with ice to obtain a mixture of 5 g of methyl (E)-4-hydroxy-3-methoxycinnamate, 25 ml of methylene chloride and 3.9 ml of triethylamine and subsequently left to react at room temperature for 60 hrs. Then, the reaction solution was filtered, concentrated slightly and chromatographed over 314 g of silica gel with methylene chloride. Crystallization from cold ethanol gave 7.03 g of 2-methoxy-4-[(E)2-methoxycarbonyl-vinyl]phenyl 4-(3-butenyloxy)benzoate.

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