4-Hydroxybenzaldehyde → Octanoic acid, 4-formylphenyl ester

Beteiligte Stoffe

Reaktionsschritte

Commercially available p-hydroxybenzaldehyde (50 g) was dissolved in pyridine (400 ml), followed by dropwise adding octanoyl chloride (80 g) under ice cooling, allowing to stand on a water bath overnight, adding toluene (300 ml), adding 6N-hydrochloric acid, separating the liquid layer, washing with 2N-NaOH aqueous solution, washing with water, drying, and distilling off toluene to obtain a raw product, distilling this product under reduced pressure to obtain p-octanoyloxybenzaldehyde (b.p. 176°~7° C./7 mmHg) (58.2 g), which was then dissolved in acetic acid (80 ml), followed by dropwise adding a mixed solution of chromium trioxide (23.4 g), water (25 ml) and acetic acid (48 ml), stirring at room temperature for 4 hours, pouring on ice, filtering the deposited solids, dissolving the solids in ethanol (300 ml), adding active carbon, shaking, filtering on heating, ice-cooling, separating the deposited crystals by filtering and recrystallizing from ethanol (300 ml) to obtain p-octanoyloxybenzoic acid (35 g). M.p. 51° C. This product (5 g) and oxalic acid chloride (7.2 g) were heated on a water bath at 60° C., followed by allowing to stand overnight, and distilling off excess oxalic acid chloride under reduced pressure to obtain p-octanoyloxybenzoyl chloride (5 g). This product was used in the following step without purification.

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