反应详情

To a suspension of 0.45 g of sodium hydride in 5 ml of anhydrous 1,2-dimethoxy-ethane a solution of 4.12 g of 2-oxoheptylphosphonic acid dimethyl ester in 20 ml of 1,2-dimethoxy-ethane was added under stirring at room temperature. The reaction mixture was stirred for an hour, then a solution of 1 g of 2-methyl-4-(6-carbomethoxyhexyl)-thiazole-5-carbaldehyde (XIII, R1 = CH3) prepared according to point (e) of Example 2, in 10 ml of 1,2-dimethoxy-ethane was added dropwise, and stirring was continued for 5 hours. After adding dropwise 30 ml of water under ice-cooling to the reaction mixture, it was extracted with 3 × 20 ml of diethyl ether. The extract was dried on over sodium sulphate and evaporated in vacuo. The evaporation residue was purified by preparative thin layer chromatography, using a silica gel layer as adsorbent and a mixture of 40 % ethyl acetate and 60 % n-heptane as running solvent. The yield was 0.81 g of 2-methyl-4-(6-carbomethoxyhexyl)-5-(3-keto-1-trans-octenyl)-thiazole (Ia, R1 = CH3) of chromatographic purity.

1. additionwas added
2. stirringThe reaction mixture was stirred for an hour
3. additionwas added dropwise
4. stirringstirring
5. temperaturecooling to the reaction mixture, it
6. extractionwas extracted with 3 × 20 ml of diethyl ether
7. dry with materialThe extract was dried on over sodium sulphate
8. customevaporated in vacuo
9. customThe evaporation residue was purified by preparative thin layer chromatography
10. additiona mixture of 40 % ethyl acetate and 60 % n-heptane