Tetrahedral cobalt(ii) complexes stabilized by the aminodiphosphine PNP ligand [PNP = CH3CH2CH2N(CH2CH2PPh2)2]

Synthesis and solid state structure of Co(II) complexes of OPTA

“…These reactions are similar to that reported by Romerosa et al in which one phosphorus of CH 3 CH 2 CH 2 N-(CH 2 CH 2 PPh 2 ) 2 was oxidized and the amine protonated upon addition to a refluxing solution of CoCl 2 Á 6H 2 O [26]. PTA has been shown to be capable of serving as a reducing agent, in the presence of water, for a variety of metals; e.g.…”

Synthesis, spectral and biological investigations of 5(2′-hydroxyphenyl)-3-(4-substituted-phenyl) pyrazolinates of cobalt(II) and their addition complexes with N, P donor ligands

“…Although it is quite difficult to comment on the molecular structure of these compounds without X-ray crystal structure analysis, a number of cobalt(II) structures have been described as tetrahedral [40][41][42][43][44]. The two pyrazoline ligands are bidentate in complexes of the type (C 15 H 12 N 2 OX) 2 Co and monodentate in the addition complexes, and tetrahedral geometry around cobalt(II) is proposed.…”

Stereospecific polymerization of 1,3-butadiene catalyzed by cobalt complexes bearing N-containing diphosphine PNP ligands

“…1. It has been reported that the addition of a third chloride, from either hydrochloric acid or ammonium chloride, to tetrahedral cobalt(II) complex with an aminodiphosphine ligand, resulted in the transfer of the third chloride to the cobalt center, even if the coordination geometry around the cobalt center was still tetrahedronal with PNP acting as a monodentate ligand through one phosphorus atom [40]. In the molecular structure of 1a, PNP atoms of the tridentate ligand are coordinated in a meridional manner, in which the P1, P2, Cl1, and Cl3 atoms could be located in an equatorial plane and the axial bonds nearly form a straight angle (N1eCo1eCl2, 179.1(2) ).…”