Ethanol, 2-chloro-, 1-(4-methylbenzenesulfonate) → 5-(2-Chloroethoxy)-2,3-dihydro-1H-inden-1-one

Beteiligte Stoffe

Reaktionsschritte

To a solution of sodium ethoxide in ethanol prepared from 5.68 g of sodium and 500 ml of absolute ethanol, 36.75 g of 5-hydroxy-1-indanone in 500 ml of slightly-heated ethanol are added in the course of 30 minutes. Then, 74.5 g of β-chloroethyl p-toluenesulphonate in 100 ml of ethanol are dropwise added, and the mixture is refluxed under stirring for 25 hours. Then the mixture is cooled, the insolubilized sodium p-toluenesulphonate 40 g, dry) is filtered off, and the ethanol is evaporated till dryness under vacuum. The residue (71.6 g) is treated with water (250 ml) and methylene chloride (250 ml); the aqueous phase is extracted two further times with methylene chloride, and the organic extracts are washed twice with 100 ml of 10% sodium hydroxide and with water till neutralization. The solvent is evaporated and the residue (54 g) is purified over silica-gel column; by eluting with methylene chloride:hexane (9:1) the excess β-chloro-ethyl p-toluenesulphonate is separated, and the desired product is isolated with methylene chloride; 26.6 g (51%) of a yellow solid are obtained. M.P. 79°-82° C. and analysis correct.

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