445460-71-9Relevant academic research and scientific papers
Synthesis and characterization of three-coordinate and related β-diketiminate derivatives of manganese, iron, and cobalt
Panda, Arunashree,Stender, Matthias,Wright, Robert J.,Olmstead, Marilyn M.,Klavins, Peter,Power, Philip P.
, p. 3909 - 3916 (2008/10/08)
Treatment of M{N(SiMe3)2}2 (M = Mn, Fe, Co) with various bulky β-diketimines afforded a variety of new three-coordinate complexes which were characterized by UV-vis, 1H NMR and IR spectroscopy, magnetic measurements, and x-ray crystallography. Reaction of the β-diketimine H(Dipp)NC(Me)CHC(Me)N(Dipp) (Dipp2N^NH; Dipp = C6H3-2,6-Pri2) with M{N(SiMe3)2}2 (M = Mn or Co) gave Dipp2N^NMN(SiMe3)2 (M = Mn, 1; Co, 3) while the reaction of Fe{N(SiMe3)2}2 with Ar2N^NH (Ar = Dipp, C6F5, Mes, C6H3-2,6-Me2, or C6H3-2,6-Cl2) afforded the series of iron complexes Ar2N^NFe{N(SiMe3)2} (Ar = Dipp, 2a; C6F5, 2b; Mes, 2c; C6H3-2,6-Me2, 2d; C6H3-2,6-Cl2, 2e). This represents a new synthetic route to β-diketiminate complexes of these metals. The four-coordinate bis-β-diketiminate complex Fe{N^N(C6F5)2}2, 4, was also isolated as a byproduct from the synthesis of 2b. Direct reaction of the Dipp2N^NLi with CoCl2 gave the ate salt Dipp2N^NCoCl2Li(THF)2, 5, in which the lithium chloride has formed a complex with Dipp2N^NCoCl through chloride bridging. The Fe(III) species Dipp2N^NFeCl2, 6, was obtained cleanly from the reaction of FeCl3 with Dipp2N^NLi. Magnetic measurements showed that all the complexes have a high spin configuration. The different substituents in the series of iron complexes 2a-e allowed assignment of their paramagnetically shifted 1H NMR spectra. The x-ray crystal structures 1-2d and 3 showed that they have a distorted three-coordinate planar configuration at the metals whereas complexes 4-6 have highly distorted four- coordinate geometries.
