Sodium hydride → (E,E,E)-7-hydroxymethyl-3,11,15-trimethyl-2,6,10,14-hexadecatetraenoic acid

Beteiligte Stoffe

Reaktionsschritte

A suspension of 14.1 g of (E)-4-methyl-5-carboxy-4-penten-1-yltriphenylphosphonium bromide, 8.4 g of (E)-1,1-dimethoxy-6,10-dimethyl-5,9-undecadien-2-one and 2.5 g of 63.8% sodium hydride in 30 ml of anhydrous dimethyl sulfoxide was stirred at 50°-55° C. for 2.5 hours and 40 ml of acetic acid-water (5:1) was added thereto. The resulting mixture was again stirred at 50°-55° C. for 30 minutes. After completion of the reaction, the reaction mixture was extracted four times with n-hexane and the extracts were washed with water, dried over anhydrous sodium sulfate and then the solvent was distilled off to leave 10.4 g of an yellow oily substance. The resulting oil was dissolved in 50 ml of ethanol, 1.2 g of sodium borohydride was added thereto at 5°-10° C. and the resulting mixture was stirred for 1 hour. To the reaction mixture were added ethyl ether and water and, after stirring, an aqueous layer was separated and neutralized with hydrochloric acid under ice-cooling. The so separated oily substance was extracted with ether and the extract was washed with water and dried over anhydrous sodium sulfate. The solvent was distilled off to afford 3.98 g of the end product.

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