3,7-Dimethylocta-2,6-Dienal → 6,10-Dimethyl-4-hydroxy-2,5,9-undecatriene

Beteiligte Stoffe

Reaktionsschritte

12 g. of magnesium turnings were suspended under nitrogen in 250 ml. of dry tetrahydrofuran. Between 60 and 65°, 60 g. of 1-bromopropene dissolved in 50 ml of tetrahydrofuran were added dropwise. During the addition, to prevent escaping of 1-bromopropene, the reflux condenser fitted on the reaction flask was cooled to -40°/-50°. When all Mg had reacted, the mixture was cooled to 20° and 76 g. of citral was added dropwise with cooling. After standing overnight, the mixture was poured into 1.5 liter of concentrated aqueous NH4Cl at 0°. The mixture was extracted 3 times with ether and the combined ether extracts treated as usual. After distillation, 6,10-dimethyl-4-hydroxy-2,5,9-undecatriene, b.p. 70°/0.1 Torr was obtained as a liquid with following constants: nD20 = 1.4950; d420 = 0.9145.

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