| 摘要 |
Preparation of 2,6-pyridine-dicarboxylic acid esters of formula (I) comprises reaction of a 2,6-dihalopyridine of formula (II) with carbon monoxide and an alcohol of formula (III) in the presence of a base and a catalyst complex from palladium and a bis-diphenylphosphine derivative of formula (IV). R1-OH (III). R1 = 1-6C alkyl, 3-6C cycloalkyl, aryl or aralkyl; R2, R3 = H or Cl; R4 = H, 1-6C alkyl, 1-6C alkoxy or F; X = Cl or Br; Q = 3-6C alkanediyl or 1,1'-ferrocenediyl (optionally containing cyclopentadienyl groups substituted by 1-4C alkyl or aryl); R5-R8 = H, 1-4C alkyl, 1-4C alkoxy, CH2F, CHF2, CF3, F, aryl, aryloxy, CN or N(alkyl)2. |
