Atom-Transfer Radical Addition Reactions Catalyzed by RuCp* Complexes: A Mechanistic Study

作者：Fernandez Zumel Mariano A; Thommes Katrin; Kiefer Gregor; Sienkiewicz Andrzej; Pierzchala Katarzyna; Severin Kay^*

来源：Chemistry - A European Journal, 2009, 15(43): 11601-11607.

DOI：10.1002/chem.200901396

• atom transfer
• homogeneous catalysis
• kinetics
• radical reactions
• ruthenium

Kinetic and spectroscopic analyses were performed to gain information about the mechanism of atom-transfer radical reactions catalyzed by the complexes [RuCl(2)Cp*(PPh(3))] and [RuClCp*(PPh(3))(2)] (Cp*=pentamethylcyclopentadienyl), in the presence and in the absence of the reducing agent magnesium. ne reactions of styrene with ethyl trichloroacetate, ethyl dichloroacetate, or dichloroacetonitrile were used as test reactions. The results show that for substrates with high intrinsic reactivity, such as ethyl trichloroacetate, the oxidation stage of the catalyst in the resting state is 3, and that the reaction is zero-order with respect to the halogenated compound. Furthermore, the kinetic data suggest that the metal catalyst is not directly involved in the rate-limiting step of the reaction.

• 出版日期2009