Mono- and bi-metallic Mn(III) complexes of macroacyclic salen type ligands: Syntheses, characterization and studies of their catalytic activity

A route to magnetically separable nanocatalysts: Combined experimental and theoretical investigation of alkyl substituent role in ligand backbone towards epoxidation ability

“…Solvents were dried according to standard procedures and distilled prior to use. Iodosylbenzene was prepared according to a literature method …”

“…The relevance of the topic encourages us to delve further, by exploring the effect of alkyl groups at the non‐aromatic chain of the ligands. For this purpose we have selected three Mn(III) and three Fe(III) Schiff base complexes, as shown in Scheme , among which 2 and 5 had been previously synthesized and tested as catalysts for the epoxidation of olefins in the presence of PhIO in CH 3 CN under mild conditions . They are included in the present work for the sake of completeness due to their close relationship with the four new catalysts here analysed.…”

Ni(II), Cu(II), and Zn(II) complexes of tetradentate schiff base containing two thiadiazoles units: Structural, spectroscopic, magnetic properties, and molecular modeling studies

“…Schiff base complexes containing different central metals such as Co, Ni, Cu, and Zn play a central role as chelating ligands in main group and transition metal coordination chemistry [1][2][3][4]. Transition metal complexes of tetradentate Schiff base ligands have been used as model analogues of certain metal enzymes [5][6][7], in catalysis and material chemistry [8][9][10][11], in various other fields such as illness treatment, biochemical reaction, and biological regulator [12], and have specific activities in pharmacology and physiology. Furthermore, the 1,3,4-thiadiazole ring system is known to possess several biological activities SCHEME 1 Synthetic route to Schiff base ligand (3).…”

Synthesis, crystal structures and catalytic abilities of new macrocyclic bis-pyridineamido MnIII and FeIII complexes

“…For example, 6 gave the yield of 94% in CH 3 CN (entry 3, Table 2), while only 69% was achieved by non-annular analogue [Mn(bpc)Cl(DMF)] [15]. Thus, the best result 95% yield could be obtained under the optimized conditions by catalyst 6, which is comparable with about 90% by Mn-porphyrin complex (2,8,12,18-tetrabutyl-3,7,13,17-tetramethyl-5,15-bis(4-pyridyl) porphyrinato manganese chloride) [36], and much higher than 79% by Salen complex [37]. The other two substrates cyclohexene and indene were also tried by this catalytic system with moderate to high yields 72% and 85%, respectively.…”