Preparation, Characterization, and Magnetic Behavior of the Ln Derivatives (Ln = Nd, La) of a 2,6-Diiminepyridine Ligand and Corresponding Dianion

An unprecedented Nd[2,6-{[2,6-(i-Pr)2C6H5]NC(CH3)}2(C5H3N)]NdI2(THF) (1) complex was prepared by oxidizing
metallic Nd with I2 in THF and in the presence of 2,6-{[2,6-(i-Pr)2C6H5]NC(CH3)}2(C5H3N). The magnetic behavior
at variable T clearly indicated that the complex should be regarded as a trivalent Nd atom antiferromagnetically
coupled to a radical anion. By using the doubly deprotonated form of the diimino pyridine ligand {[2,6-{[2,6-(i-Pr)2C6H5]N−CCH2}2(C5H3N)]2- (2) the corresponding trivalent complexes {[2,6-{[2,6-(i-Pr)2C6H5]N−CCH2}2(C5H3N)]Ln (THF)}(μ-Cl)2[Li(THF)2]·0.5 (hexane) [Ln = Nd (3), La (4)] were obtained and characterized. Reduction
of these species afforded electron transfer to the ligand system which gave ligand dimerization via C−C bond
formation through one of the two ene-amido functions of each molecule. The resulting dinuclear {[{[2,6-(i-Pr)2C6H5]N−C(CH2)}(C5H3N){[2,6-(i-Pr)2C6H5]NCCH2}]Ln(THF)2(μ-Cl)[Li(THF)3]}2·2(THF) [Ln = Nd (5), La (6)] were isolated
and characterized.