Synthese und Charakterisierung neuer fünf‐ und sechsfach koordinierter Mangan(II)‐Komplexe als Modellsysteme für manganabhängige Catecholdioxygenasen

Abstract

Synthesis and Characterization of Novel Five‐ and Six‐coordinate Manganese Complexes as Catechol Dioxygenase Models The five‐ and six‐coordinate manganese complexes [Mn(tphhp)Cl2] {tphhp = N,N′‐bis(2‐pyridylmethyl)‐2‐(2‐pyridyl)hexahydropyrimidine} (1), [Mn(bpma)Cl](ClO4) {bpma = bis((2‐pyridylmethyl)((1‐methylbenzimidazol‐2‐yl)‐methyl)amine} (2) and [Mn(L)TCC] {HL = (1‐hydroxy‐4‐nitrobenzyl)((1‐methylimidazol‐2‐yl)methyl)(2‐pyridylmethyl)amine} (3) were synthesized and characterized by various techniques such as single crystal X‐ray structure analysis, mass spectrometry, IR and UV/vis spectroscopy, cyclic voltammetry, and elemental analysis. 1 and 2 crystallize in the monoclinic space group P21/n (No. 14) (1) and P21/c (No. 14) (2). The ligand and the chlorine ions provide the N3Cl2‐donorset in 1 and the N3Cl2‐donorset in 2, respectively. Compounds 1 and 2 show catalytic activity regarding the oxidation of 3,5‐di‐tertbutylcatechol to 3,5‐di‐tert‐butylchinon. To our knowledge, 1 and 2 are the first five‐coordinate manganese complexes that show catecholase activity. 3 crystallize in the orthorhombic space group P212121 (No. 19) and the ligand and tetrachlorocatechol (TCC) build the N3O3‐donorset in 3.

Antiferromagnetic Porous Metal–Organic Framework Containing Mixed-Valence [MnII4MnIII2(μ4-O)2]10+ Units with Catecholase Activity and Selective Gas Adsorption

“…The oxidation process of 3,5-DTBC to 3,5-DTBQ involves two electrons. Literature survey reveals that higher valent metal centers (e.g., Cu II , Mn III and Mn IV ) , are usually involved in catechol oxidation; the reports on catecholase activities of manganese(II) complexes are relatively rare . The manganese centers are in +2 and +3 oxidation states in the present complex.…”

Synthesis, Crystal Structure, and Catecholase Activity of Three Trinuclear Heterometallic NiII2–MnII Complexes Derived from a Salen‐Type Schiff Base Ligand

“…Catecholase activity of manganese complexes is mostly observed with the higher valent Mn(III/IV) 14. This activity is very rare for complexes that have a Mn II center 14a,14c,32a. The catecholase activity of some dinuclear Ni II complexes has been recently reported 15.…”

Tris(guanidinato)complexes of iridium and rhodium in the oxidation states +III and +IV

“…In fact, L2 is a new ligand, and it is worth noting that while L1 and its Mn II complex were previously reported, but no experimental details were given. 121 Other routes for the synthesis of L1 and L2 were also considered and executed (Scheme A4 and A5). For both routes, the first step could result in reasonable yields, but only low yields could be obtained in the second step.…”