反应详情

In 7 ml of methanol were dissolved 1.61 of N-methyl-α-picolinium iodide and 1.70 g of p-formylphenoxyacetaldehyde dimethyl acetal. The resultant mixture, after addition thereto of 0.3 ml of piperidine, was refluxed for four hours. When the reaction solution was cooled, there ensued precipitation of crystals. The crystals were recovered, washed with a small amount of cooled methanol and washed thoroughly with acetone. Thus, there was obtained 2.11 g of 1-methyl-2-{p-(2,2-dimethoxyethoxy)-styryl}-pyridinium iodide having a melting point of 192° to 197° C. By following the same procedure, but using the n-methyl-α-picolinium iodide in combination with m-formylphenoxyacetaldehyde dimethylacetal and n-methyl-γ-picolinium p-tolunesulfonate in combination with p-formylphenoxyacetaldehyde dimethylacetal, as the raw materials, there were respectively obtained 1-methyl-2-{m-(2,2-dimethoxyethoxyl)-styryl}-pyridinium iodide having a melting point of 181° to 186° C., 1-methyl-2-{o-(2,2-dimethoxyethoxy)-styryl}-pyridinium iodide having a melting point of 169° to 173° C., and 1-methyl-4-{p-(2,2-dimethoxyethoxy)-styryl}-pyridinium p-toluenesulfonate having a melting point of 219° to 226° C.

1. temperatureWhen the reaction solution was cooled
2. customprecipitation of crystals
3. customThe crystals were recovered
4. washwashed with a small amount of cooled methanol
5. washwashed thoroughly with acetone