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Upstream product

• 90-02-8 salicylaldehyde 
• 811-93-8 1,1-dimethylethylenediamine 
• 89-95-2 2-methyl-benzyl alcohol 

Relevant academic research and scientific papers

Steric influence of salicylaldehyde-based Schiff base ligands on the formation of: Trans-[Re(PR3)2(Schiff base)]+ complexes

Complexes of the type trans-[Re(PR3)2(Schiff base)]+ (R = ethyl and/or phenyl) 2-7 were prepared by the reaction of (nBu4N)[ReOCl4] with H2sal2en or H2sal2ibn followed by addition of a tertiary phosphine. The trans-[Re(PR3)2(sal2en)]+ complexes 2-4 were stable in solution, whereas the trans-[Re(PR3)2(sal2ibn)]+ complexes 6-7 were observed to convert to their corresponding cis-[ReO(PR3)(sal2ibn)]+ products through a process involving ligand dissociation, metal oxidation, and Schiff base ligand rearrangement. The conversion of the trans-[Re(PR3)2(sal2ibn)]+ complexes is likely driven by steric interactions between the bulky backbone gem-dimethyl groups of the sal2ibn ligand and the phosphine ligands. These complexes were isolated and characterized by 1H and 13C NMR, FT-IR spectroscopy, cyclic voltammetry, and single crystal X-ray diffraction. The results reported herein provide insight into the factors that drive trans-[Re(PR3)2(Schiff base)]+ complex formation. This will aid in the development of novel 186/188Re therapeutic agents and the design of novel bifunctional N2O2 Schiff base ligands.

Structure, magnetic properties and epoxidation activity of iron(III) salicylaldimine complexes

Two new iron(m) complexes with salicylaldimine ligands, [Fe(L')Cl]-CH3CN (1) and [Fe(L2)CI(H2O)]-l/3CHjCI (2) [H2L! = AW-O.l-dimethylethyleneJbistsalicylaldimine), H2L2 = Ar,Ar'-(l,l-dimethylethylene)bis(3-methoxysalicylaldimine)], have been prepared and characterized. The X-ray crystal structure analysis shows that the iron(in) ion in complex 1 is in a distorted square pyramidal environment, while in 2, the iron(ni) center is six-coordinate with distorted octahedral geometry. The Schiff base ligands L' and L2 occupied the basal sites, with chloride and water occupying the apical sites. Magnetic susceptibility and Moessbauer effect measurements showed a high-spin configuration (S=5/2) for Fe(ni) in 1 and 2. The temperature dependence of the magnetic data for complexes 1 and 2 is analyzed in terms of the spin-Hamiltonian formalism, which gives an accurate estimate of the zero-field splitting of the ground state of the iron(in) ions as D = 10.2 cm"1 (￡=3.4 cm"1) and D = 7.2 cm"1 (￡=2.4 cm"1, zJ' = -0.5 cm"1), respectively, in the above two complexes. It has been found for the first time that complexes 1 and 2 activate the epoxidation of cw-stilbene by NaOCl. With 1, the epoxides were produced in 40% yield with cis: trans = 20:80, and with 2, the epoxides were produced in 90% yield with cis-.trails = 40:60. The Royal Society of Chemistry 2000.

New compounds of tetradentate Schiff bases with vanadium(IV) and vanadium(V)

A new range of potentially tetradentate proligands, H2L, derived from aromatic aldehydes and ketones and aliphatic diamines has been prepared. Their vanadyl(IV) and vanadyl(V) complexes [VO(L)] and [VO(L)]+, and also some adducts [VO(L)→VO(L)]+, have been synthesized. The structures of four selected complexes have been determined and it is shown that these must be a result of both steric and electronic factors that make prediction of conformation and stacking difficult. The adducts [VO(L)→VO(L)]+ have structures that persist in solution in dichloromethane, where they can undergo redox chemistry, but they apparently dissociate into their component complexes in the donor solvent acetonitrile. The Royal Society of Chemistry 1999.

[N,N′-bis(salicylidene)-1,2-diimino-2-methylpropane]copper(II)

In the title compound, [Cu(C18H18N2O2)], the coordination geometry about the Cu atom is a 6-5-6 chelate ring structure, with a tetrahedrally distorted square plane composed of two imine N atoms and two phenol O atoms. The angle between the two planes, which each contain the donor atoms of a salicylaldiminato residue, and the central Cu atom is 15.8(2)°.