The reduction of CpTi(NPt-Bu-3)Cl-2 with Mg powder in benzene proceeds slow
ly to give [CpTi(NPt-Bu-3(mu-Cl)](2))12 tli. An X-ray crystallographic stud
y confirmed 1 is a centrosymmetric chloro-bridged dimer in the solid state.
A single-crystal EPR study of 1 permitted the determination of the best-fi
tted values for the diagonal spin Hamiltonian parameters. This appears to b
e the first EPR single-crystal study of a Ti(III)-Ti(III) dimer. The implic
ations of these data are considered and discussed in light of extended Huck
el molecular orbital calculations.