反应详情

A solution of 2 -ethyl-2-(6-methoxy-2-naphthyl)-1,3-dioxolane-4(R),5(R)-dicarboxylic acid dimethyl ester (0.935 g, 2.5 mmol) and of iodine monochloride (0.81 g, 5 mmol) in dichloromethane (5 ml) is kept under nitrogen and at 15° C. for 24 hours. The reaction mixture is poured into a 10% aqueous solution of sodium bicarbonate, and extracted with additional dichloromethane. The combined organic extracts are washed with a 5% aqueous solution of sodium thiosulphate, with water, dried (Na2SO4), filtered, and concentrated in vacuo. Purification of the residue by column chromatography (silical gel, eluent hexane:diethyl ether=7:3) gives the diastereoisomeric mixture of 2-(1-iodoethyl)-1-iodoethyl)-2-methoxy-2-naphthyl)-1,3-dioxolane-4(R),5(R)-dicarboxylic acid dimethyl ester 15 and 16 in ratio 15:16=60:40 (determined by 1H-NMR).

1. extractionextracted with additional dichloromethane
2. washThe combined organic extracts are washed with a 5% aqueous solution of sodium thiosulphate, with water
3. dry with materialdried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customPurification of the residue by column chromatography (silical gel, eluent hexane:diethyl ether=7:3)
7. customgives