| 摘要 |
A novel method for generating dianions using 3-methylpyridine-2-carboxylic acid derivatives of formula (V) or using their corresponding alkali metal salts of formula (VI), preferably from their lithium salt (Scheme 3) is described. The substituents R<1>, R<2>, R<3>, R<4>, R<5>, R<6> and R<7> in Scheme 3 are defined as herein described above. Preferably the substituents are selected from one or more of hydrogen, halogen or C1-C6 alkyl groups. M is represented by any alkali metal ion, preferably lithium. |
