Abstract
Cobalt and nickel complexes of 4-methyl-2,6,7-trioxa-l-phosphabicyclo[2.2.2]octane (I), the 4-ethyl analog of I (I'), and 2,8,9-trioxa-l-phosphaadamantane (II) are described. Maximum coordination numbers for the metals are observed for
the yellow [Co(P(OCH2)3CCH2CH3)6] +, colorless [Co(P(OCH2)3CCH2CH3)6] +3, yellow [Co(P(OCH)3(CH2)3)6]+, and color- less [Co(P(OCH)3(CH2)3)e] +3 ions, all of which are diamagnetic. Calculations of Dq from ultraviolet spectra of the colorless cobalt complexes show that I' and II provide ligand fields of about the same strength as that of the cyanide ion. The yellow diamagnetic [Ni(P(OCH2)3CCH3)6]+2, [Ni(P(OCH2)3CCH2CH3)6]+2, and [Ni(P(OCH)3(CH2)3)6] +a ions are also de- scribed and their possible configurations discussed. The reduction of the [NiL3] +2 ions (where L = I, I', or II) to the corre- sponding N1L4 complexes wherein nickel is zerovalent is also reported.