Recent developments in supramolecular complexes of azabenzenes containing one to four N atoms: synthetic strategies, structures, and magnetic properties

Abstract

A summary of azabenzene-based ligands, having one to four N atoms, and their binding modes with different metals ions and magnetic properties are highlighted in this article based on recent publications.

Structure, Optical and Magnetic Properties of Two Isomeric 2-Bromomethylpyridine Cu(II) Complexes [Cu(C6H9NBr)2(NO3)2] with Very Different Binding Motives

“…Both are constant over a wide temperature range and within the range from 1.7 to 2.2 µ B experimentally observed for similar Cu(II) complexes at room temperature [ 25 , 64 , 65 , 66 , 67 , 68 , 69 , 70 ]. The effective moments being larger than the spin-only value of 1.73 µ B expected for a 3d 9 configuration ( S = 1/2) indicate spin-orbit coupling [ 23 , 37 , 39 , 64 , 65 ].…”

“…The Weiss constants of −1 K ( CuL 1 ) and −1.5 K ( CuL 2 ) are comparably small. A Weiss constant >0 indicates dominating ferromagnetic interactions and for <0 dominating antiferromagnetic interactions [ 23 , 64 ]. Thus, we can attribute a weak antiferromagnetic character to both complexes.…”

“…Additionally, the nature of the ligand combined with the h ard and s oft a cids-and b ases principle (HSAB) help in taming the quite flexible geometries of many 3D transition metals. Thus, using the very simple synthesis approach of mixing ligands and transition metal precursors in solution and precipitating or crystallizing the products, defined materials with interesting catalytic [ 17 , 18 , 19 , 20 , 21 ], electrochemical [ 21 , 22 ], magnetic [ 23 , 24 , 25 ], photochemical [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ], and photophysical properties [ 30 , 31 , 32 , 33 , 34 , 35 ] have been obtained in good yields.…”

“…Cu(II) is an interesting metal for magnetic materials due to its unpaired spin ( S = ½) in its d 9 configuration. The careful design of polyfunctional ligands has allowed to generate dinuclear or oligonuclear Cu(II) coordination compounds with paramagnetic (isolated spins) [ 24 , 33 ], antiferromagnetic (two coupled spins) [ 23 , 36 ], ferromagnetic [ 37 , 38 ], or ferrimagnetic (coupled spins of different species) properties [ 23 , 36 , 39 , 40 , 41 , 42 ].…”

Recent advances in versatile pyridazine-cored materials: principles, applications, and challenges

“…49,147 For the sake of more and better functional PD-ringbased materials, herein, the general strategy can be explored by combining the previous studies and interesting results with practical synthetic methodologies (Scheme 7), 50,106,[148][149][150][151][152][153][154][155][156] theoretical calculations, 129,[157][158][159][160][161] aza-quantity effect and azaregioisomerism, 159,160 and supramolecular strategies, 29,[162][163][164][165] the serendipitously discovered or well-designed of PD-based materials possess huge application prospects in the fields of optoelectronics, chromism, fluorescence probes, and energy materials. The unceasing breakthroughs in catalysis, 9,45,115,154,166,167 magnetic complexes, 155,168 molecular rotators (Fig. 8b), 162 and high strength/stiffness nanothreads 32,169,170 are worthy of further investigation and devotion (Fig.…”