Chelating alkoxo/amido-phosphines are rare ligand platforms for late metals. Presented here is a new family of iron(II) alkoxo/amido complexes and investigation on their reactivity. Carbonyliron(0) compounds promote the reductive coupling of the phosphinoimine Ph2PC6H4CHNC6H4Cl and the phosphinoaldehyde Ph2PC6H4CHO, respectively, to give tetradentate C2-symmetric dianionic ligands in complexes with the general formula Fe[(Ph2PC6H4)2C2H2X2](CO)2 (Figure 1). Attempted oxidation of these complexes by ferrocenium salts results in C-C bond cleavage of the ligand. The alkoxo and amido functionalities are basic and react with Lewis acids to form adducts. The Fe-O bond can be cleaved by addition of silanes to form hydrido complexes. This mode of Si-H activation has not been reported for iron complexes. One CO ligand in Fe[(Ph2PC6H4)2C2H2O2](CO)2 is labile, and reaction with acetonitrile gives Fe[(Ph2PC6H4)2C2H2O2](CO)(MeCN), which is an active catalyst for hydrosilylation of carbonyls and styrene. Possible mechanisms of which will be discussed.

Tetradentate dianionic diphosphino ligands: New ligand platforms for iron(II) complexes

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.