The reaction of Ru(CO)2(MeCO2)2(PR3)2 or Ru2(CO)4(MeCO2)2(PR3)2 [RBu, Ph] with H2 in the presence of Na2CO3: a stoichiometric carbon dioxide activation

Autor: Cristina Faggi, Franco Piacenti, Piero Frediani, Antonella Salvini, Mario Bianchi
Rok vydání: 1998
Předmět:
Zdroj: Inorganica Chimica Acta. 272:141-149
ISSN: 0020-1693
DOI: 10.1016/s0020-1693(97)05973-2
Popis: The hydrogenolysis of the acetato group by molecular hydrogen in phosphine-substituted ruthenium(I) and (II) carbonyl carboxylates has been reinvestigated in the presence of Na2CO3 at various temperatures. From mononuclear complexes such as Ru(CO)2(MeCO2)2(PR3)2, the intermediate hydrido-acetato complex HRu(CO)2(MeCO2)(PR3)2 has been identified among the products formed working at low temperature. In the case of the binuclear complexes Ru2(CO)4(MeCO2)2(PR3)2 the products obtained at the lowest reaction temperature are H4Ru4(CO)9(PR3)3, H4Ru4(CO)8(PR3)4 and H2Ru(CO)2(PR4)2. The complex H4Ru4(CO)9(PR3)3 is formed from H4Ru4(CO)8(PR3)4 and CO produced from carbon dioxide by the reverse water gas shift reaction catalysed by ruthenium complexes: CO 2 +H 2 ⇄ | Ru | CO+H 2 O Carbon dioxide arises from the reaction between Na2CO4 and acetic acid. Several tests support the involvement of the ruthenium-catalysed reverse water gas shift reaction. At higher temperatures phosphido ruthenium complexes are formed. The same products are obtained in the absence of carbon dioxide.
Databáze: OpenAIRE
Externí odkaz: