76898-63-0Relevant academic research and scientific papers
3.5-Dimethylpyrazolylphosphine molybdenum(0) and tungsten(0) carbonyl complexes
Davis, Harry B.,Hoyano, James K.,Leung, Ping Yuen,Peterson, Louis K.,Wolstenholme, Brian
, p. 151 - 158 (2007/10/02)
Complexes with general formula nM(CO)m>, where L=ΦxP(Me2pz)3-x, x=0-2, n=1 or 2, M=Mo(0) or W(0), m=3 or 4, were prepared by thermal or photolytic methods by the reaction of the appropriate 3,5-dimethylpyrazolyl phosphine ligand with M(CO)6, norbornadienemetaltetracarbonyl 4>, cycloheptatrienylmetaltricarbonyl 3>, 2N(CH2)3NMe2)M(CO)4>, 2M(CO)4>, or 3M(CO)3>.Structural evidence indicates octahedral geometry about the metal atom centre, and several modes of coordination for the ligands in those complexes isolated and characterized.For x=2, the ligand Φ2P(Me2pz) was monodentate, via phosphorus in 2P(Me2pz))2M(CO)4> (I,II), and bidentate in 2P(Me2pz)M(CO)4> (III, IV) where coordination by P and the 2N site of the pyrazolyl ring yielded four-membered MPNN metallocycles.For x=1, the ΦP(Me2pz)2 ligand was bidentate, via the phosphorus atom and one of the 2N sites of one of the pyrazolyl substituents, thus giving the four-membered MNNP metallocycle in 2pz)2W(CO)4> (V), and tridentate in 2pz)2M(CO)3> (VI, VII) where three facial CO's, two 2N atoms of the pyrazolyl rings, and a part of the phenyl ring occupy the six coordination sites.For x=0, the P(Me2pz)3 ligand was tridentate via the 2N atoms of all three pyrazolyl rings, thus giving tricyclic systems 2pz)3M(CO)3> (VIII, IX).
