反应详情

A mixture of 6.8 parts of imidazole, 8.5 parts of B -2-(bromomethyl)-4-(p-chlorophenoxymethyl)-2-(2,4-dichlorophenyl)-1,3-dioxolane, 2 parts of sodium iodide and 100 parts of dimethylformamide is stirred and refluxed for 36 hours. The reaction mixture is allowed to cool to room temperature and poured into water. The product is extracted twice with benzene. The combined organic layers are washed twice with water, dried and the solvent is removed in vacuo. The residue is purified by column-chromatography over silica gel using chloroform as eluent. The pure fractions are collected and the eluent is evaporated. The residue of B-1-[4-(p-chlorophenoxymethyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-2-ylmethyl]-imidazole is converted into the oxalate salt in 4-methyl-2-pentanone: upon the addition of diisopropylether, the salt is precipitated. It is filtered off and crystallized from 4-methyl-2-pentanone, yielding 3.1 parts of trans-1-[4-p-chlorophenoxymethyl)-2-(2,4-dichlorophenyl)-1,3-dioxolan-2-ylmethyl]-imidazole sesquioxalate; mp. 101°C.

1. temperaturerefluxed for 36 hours
2. extractionThe product is extracted twice with benzene
3. washThe combined organic layers are washed twice with water
4. customdried
5. customthe solvent is removed in vacuo
6. customThe residue is purified by column-chromatography over silica gel
7. customThe pure fractions are collected
8. customthe eluent is evaporated
9. additionupon the addition of diisopropylether
10. customthe salt is precipitated
11. filtrationIt is filtered off
12. customcrystallized from 4-methyl-2-pentanone