Some new 2,6-bis(diphenylphosphinomethyl)pyridine (pnp) complexes of Ni(II), Co(II), and Fe(II) were prepd. and their phys. properties were detd. and compared with those of some previously described Ni(II) complexes. A 5-coordinate mol. structure (distorted trigonal bipyramidal), instead of the previous square-planar, is now suggested for [Ni(pnp)2]2+. For Ni(pnp)(NCS)2, previously described as a mixt. of low-spin and high-spin forms of a 5-coordinated mol., the formulation [Ni(pnp)NCS][Ni(pnp)(NCS)3], which receives strong support from the exptl. data, is suggested. The 6-coordinated Ni(pnp)(NO3)2, the 5-coordinated high-spin Co(pnp)(NO3)2 and Fe(pnp)(NO3)2, and the 6-coordinated low-spin [Co(pnp)2](ClO4)2 and [Fe(pnp)2](ClO4)2 are also described. The equil. const. for the hydration reaction of Ni(pnp)Cl2 in BuOH-H2O soln. is detd.
2,6-Bis(diphenylphosphinomethyl)pyridine complexes of nickel(II), cobalt(II), iron(II)
VASAPOLLO, Giuseppe;
1982-01-01
Abstract
Some new 2,6-bis(diphenylphosphinomethyl)pyridine (pnp) complexes of Ni(II), Co(II), and Fe(II) were prepd. and their phys. properties were detd. and compared with those of some previously described Ni(II) complexes. A 5-coordinate mol. structure (distorted trigonal bipyramidal), instead of the previous square-planar, is now suggested for [Ni(pnp)2]2+. For Ni(pnp)(NCS)2, previously described as a mixt. of low-spin and high-spin forms of a 5-coordinated mol., the formulation [Ni(pnp)NCS][Ni(pnp)(NCS)3], which receives strong support from the exptl. data, is suggested. The 6-coordinated Ni(pnp)(NO3)2, the 5-coordinated high-spin Co(pnp)(NO3)2 and Fe(pnp)(NO3)2, and the 6-coordinated low-spin [Co(pnp)2](ClO4)2 and [Fe(pnp)2](ClO4)2 are also described. The equil. const. for the hydration reaction of Ni(pnp)Cl2 in BuOH-H2O soln. is detd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
