Hydrochloric Acid → 4-(1-Indanyl)-1-butanol

Beteiligte Stoffe

Reaktionsschritte

A suspension of activated zinc (40 g) in dry tetrahydrofuran (150 ml) was heated to reflux and a few crystals of iodine was added. A solution of 1-indanone (50 g) and methyl 4-bromo-crotonate (100 g) in 400 ml of dry tetrahydrofuran was added dropwise followed by reflux for 1 h. After cooling, ice was added and the pH adjusted to 1 with concentrated hydrochloric acid followed by extraction with dichloromethane. Concentration of the organic phase left a viscous oil which was dissolved in methanol (400 ml). Concentrated hydrochloric acid (100 ml) was added and the mixture stirred for 30 min. Removal of solvents in vacuo, addition of water, and extraction with ether gave, after drying over magnesium sulfate and removal of solvent in vacuo, an oil (34 g). The oil was dissolved in 300 ml of dry ether and added dropwise to a suspension of lithium aluminium hydride (21 g). After reflux for 2 h, the reaction mixture was hydrolyzed with water. Filtration and removal of solvent in vacuo gave a mixture of isomers from which 4-(1-indanyl)-but-3-en-1-ol (6 g) could be isolated by column chromatography (silica gel, eluent: dichloromethane/ether=9:1). The remaining mixture of isomers (9 g) was dissolved in 150 ml of methanol and hydrogenated at 3 atm of hydrogen pressure in a conventional Parr apparatus in the presence of 5% palladium on charcoal (6 g) for 12 h. Filtration and removal of solvent in vacuo gave 6 g of 4-(1 -indanyl)-1-butanol.

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