反应详情

A mixture of 1 g of 3-formyl-4-methyl-pent-3-ene-1-oic acid, 25 ml of anhydrous ether and 1 g of lithium chloride was stirred under a current of gaseous hydrogen chloride at -30° C. for 2 hours and then for 2 hours at 0° C. after which the gaseous hydrogen chloride was shut off. The mixture was stirred at room temperature for 48 hours and after 54 hours of contact, the mixture was poured into iced water. The decanted aqueous phase was extracted with benzene and the organic phase was dried and evaporated to dryness under reduced pressure. The 1.1 g of residue was chromatographed over silica gel and was eluted with a 1-1 benzene-ethyl acetate mixture to obtain 545 mg of crystalline (dl trans 4-(2-chloro-prop-2-yl)-5-hydroxy-tetrahydrofuran-2-one melting at 80° C.

1. extractionThe decanted aqueous phase was extracted with benzene
2. customthe organic phase was dried
3. customevaporated to dryness under reduced pressure
4. customThe 1.1 g of residue was chromatographed over silica gel
5. washwas eluted with a 1-1 benzene-ethyl acetate mixture