The reaction of lithio derivatives of TTF (tetrathiafulvalene) derived from TTF 1 and LDA in ether solution with 4-oxo-TEMPO (2,2,6,6-tetramethylpiperidine-N-oxy)gave 4-hydroxy-TEMPO-substituted TTF derivative 2. The magnetic susceptibility and magnetization data on polycrystalline samples of 2 as well as their CT complexes withI2, DDQ or TCNQF4revealed only weak intra- or intermolecular antiferromagnetic interactions between unpaired electrons. The decrease of magnetic susceptibility by CT formation together with their solid ESR data showing the decrease of absorption intensity suggested antiparallel spin formation between unpaired electrons in CT complexes.