K. Heinze et al., COMPLEXES OF COBALT(II) CHLORIDE WITH THE TRIPODAL TRISPHOSPHANE TRIPHOS - SOLUTION DYNAMICS, SPIN-CROSSOVER, REACTIVITY, AND REDOX ACTIVITY, Inorganic chemistry, 36(24), 1997, pp. 5457-5469
Depending on the reaction conditions, different products are obtained
from the reaction of CoCl2 with CH3C(CH2PPh2)(3) (triphos), including
the law-spin complexes [(triphos)Co(mu-Cl)(2)Co(triphos)](2+) (1(2+))
and [(triphos)CoCl2] (3), their solid-state structures being determine
d by X-ray methods. In solution, additionally, a four-coordinate high-
spin complex [(eta(2)-triphos)CoCl2] (2) is present, its concentration
relative to that of 3 depending on the solvent and the temperature. T
he reactivity of these species toward Lewis acids is investigated lead
ing to the novel heterodinuclear complexes [(triphos)Co(mu-Cl)(2)MCl2]
(M = Fe (5), Co (6)). Reactions with Lewis bases L yield complexes of
the rare type [(triphos)CoCl(L)](+) (L = CO (7(+)), PMe3 (8(+)), NH3
(9(+)), CH3CN (10(+))). One electron reduction of 3 leads to the previ
ously prepared pseudotetrahedral [(triphos)(CoCl)-Cl-I] complex 11, an
d one-electron oxidation to the novel trigonal-bipyramidal low-spin co
mplex [(triphos)(CoCl2)-Cl-III](+) (12(+)).