(1)H, (13)C, (14)C, (19)F NUCLEAR MAGNETIC RESONANCE CONTACT SHIFTS AND ELECTRON SPIN DISTRIBUTION IN ANILINE AND FLUOROANILINES‐NI(II) ACETYLACETONATE COMPLEXES

C. CHACHATY, A. FORCHIONI, and J. VIRLET. Can. J. Chem. 53,648 (1975). The contact shifts of 'H, 13C, 14N, and 19F in chloroform solutions of Ni(I1) acetylacetonate aniline and fluoraniline complexes have been studied by high resolution n.m.r. The unpaired electron spin distribution in these ligands is compared to that calculated by the INDO method for the corresponding aniline cation radicals. The ratio of the hyperfine coupling constants .H aNHH/aN suggests that in these aniline complexes the c,-N' fragment is pyramidal with an \H angle of 13-15" between the perpendicular of the C-N bond and the axis of the p like orbital centered on nitrogen. The electron spin distribution between the NHZ group and the phenyl ring may be partially accounted for by assuming an internal rotation about the C-N bond. The 13C relaxation indicates a N-Ni distance of the order of 2 A for aniline and 2 fluoraniline complexes and an electron spin-lattice relaxation time of -5 x 10-lo s at 300 OK.