Reactions of Zerovalent Ruthenium Complexes with Maleic Anhydride or Maleimides:Ligand Displacement vs Oxidative Cyclization

摘要

The reactions of Ru(eta~6-cot)(dmfm)_2(1;eta~6-cot = 1,3,5-cyclooctatriene,dmfm = dimethyl fumarate)and Ru(eta~4-cod)(eta~6-cot)(2;eta~4-cod = 1,5-cyclooctadiene)with maleic anhydride or maleimides were investigated.The former reaction gave a series of novel zerovalent complexes 4 via ligand displacement between dimethyl fumarate and added electron-deficient olefins.In contrast,oxidative cyclization proceeded in the latter case to afford divalent eta~5-pentadienyl complexes 5,which further reacted with CO giving tricarbonyl complex 6.