反应详情

The same synthesis procedures as in Example 1 were conducted except for using 2-chloro-5-cyanopyridine and 1,4-dioxane-2,3-diol in place of 4-cyanopyridine and a 40% glyoxal aqueous solution, respectively, and, after completion of the reaction, the organic layer was distilled under reduced pressure of 3.0 to 3.1 Torr to obtain a 150 to 152° C. fraction. Thus, there was obtained 151.0 g (yield: 82.5%) of the end product as pale yellow crystals. HPLC analysis revealed that purity of the product was 99.1%.

1. customThe same synthesis procedures as in Example 1
2. distillationthe organic layer was distilled under reduced pressure of 3.0 to 3.1 Torr
3. customto obtain a 150 to 152° C. fraction