The novel, hemilabile (phosphinoalkyl)arene ligands ArX(CH2)2PPh2 (1a, Ar = C6H5, X = O; 1b, Ar = C6H5, X = CH2; 1c, Ar = FC6H4, X = CH2) were synthesized and complexed to Rh(I) to form the bis(phosphine), η6-arene piano stool complexes [(η6:η1-ArX(CH2)2PPh 2)Rh(η1-ArX(CH2)2PPh 2)]BF4 (2a-c). Complexes 2a-c were fully characterized in solution, and complex 2a was characterized by single-crystal X-ray diffraction methods. Two of these complexes, 2a,c, undergo an unusual, degenerate η6-arene, free arene exchange reaction which was studied by 2-D NMR EXSY experiments. A mechanism for the exchange reaction of 2a which involves the formation of a square planar, cis-phosphine, cis-ether Rh(I) complex, [Rh(η2-PhO(CH2)2PPh2) 2]BF4 (13), is proposed.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry