Di- and TrimanganeseN,N′-Dicyclohexylformamidinate Complexes

Abstract

The reaction of [MnCl 2 (thf) 2 ] with the N,N'-dicyclohexylformamidinate anion gave two remarkably different results depending on the nature of the amidinate alkali metal countercation. The reaction with the lithium salt affords a mixed-valence Mn ± oxo cluster [Mn 3 (CyNCHNCy) 6 OLi]´2 THF (1), formed by the deoxygenation of THF. In the case of the potassium salt, a dinuclear complex [{(CyNCHNCy)-Mn} 2 (m-CyNCHNCy) 2 ] (2) was formed; it has a highly distorted structure. The complexes 1 and 2 are both extremely sensitive to oxygen. Reaction of 2 with dry O 2 afforded the dinuclear complex [{Mn(CyNCHNCy) 2 } 2 (m-O)] 2´2 THF (4).

Bis(arylimido) Molybdenum(VI) Amidinate and Guanidinate Complexes; Molecular Structures of [(ArN)2MoMe{N(Cy)C[N(i-Pr)2]N(Cy)}] (Ar = 2,6-i-Pr2C6H3; Cy = Cyclohexyl) and [(2,6-i-Pr2C6H3N)2MoCl2] · [NH=C(C6H5)CH(SiMe3)2]

“…2000, 626, 1660±1664 Table 3 Crystal data and structure refinement parameters for compounds 7 and 8. 7 8 …”

“…It is our recent interest to investigate this class of compounds having other bidentate ligands with expectation to have an insight into the coordination sphere of Mo and the effect of ligand properties. Bidentate anionic amidinate and guanidinate ligands are very important ancillary ligands in transition and main group metal chemistry and have been widely used for Group 13 [2] and 14 [3] metals as well as for Group 4 [4], 5 [5], 6 [6] and 7 metals [7]. Due to the variability of the substituents on the backbone of these ligands, it seems that these ligands are suitable for our studies.…”

The oxygen scavenging properties of alkali metal-containing organometallic compounds

“…It has been reported that the 1+2 reaction of (THF) 4 •MnCl 2 with lithium N,NA-dicyclohexylformamidinate in THF yields highly air-sensitive crystals which X-ray diffraction shows to be composed of the mixed-valence Mn(II)-Mn(III) oxide-encapsulation complex LiMn 3 [CyNC(H)NCy] 6 (O) 46 (Cy = cyclohexyl). 31 The oxide ion resides at the centre of a heavily disordered tetrahedral array of metal centres while each of the six formamidinate ligands bridges an edge of the polyhedron. The organic residues do not lie coplanar with the two bridged metal centres but are skewed, causing the N-centres to adopt a slightly pyramidal geometry.…”

13 Manganese, technetium and rhenium

“…46a Other reports on these compounds also discuss , with each L bridging a tetrahedron edge. 50 Two 1,3-diaminopropane molecules react with two molecules of 2,2 H -benzyl-5,5 Hdiformylpyrrole to give a binucleating ligand that can co-ordinate two Mn 2 ions from Mn(II) acetate, with one acetate bridge. The complex, whimsically described as an accordion porphyrin, shows catalase behaviour.…”