The synthesis of new Schiff base-like ligands with asymmetric substituents pattern and their iron complexes with pyridine as axial ligand is described. Two of the ligands and one of the iron(II) complexes were characterized by single crystal X-ray structure analysis. One of the the iron(II) complexes shows spin crossover behavior while the others remain in the high spin state. The influence of the reduced symmetry of the ligand on the properties of the complexes is discussed.
. [J]. Frontiers of Chemical Science and Engineering, 2018, 12(3): 400-408.
Wolfgang Bauer, Tanja Ossiander, Birgit Weber. Synthesis of iron(II) complexes with asymmetric N2O2 coordinating Schiff base-like ligands and their spin crossover properties. Front. Chem. Sci. Eng., 2018, 12(3): 400-408.
Catala L, Mallah T. Nanoparticles of Prussian blue analogs and related coordination polymers: From information storage to biomedical applications. Coordination Chemistry Reviews, 2017, 346: 32–61 https://doi.org/10.1016/j.ccr.2017.04.005
2
Ferrando-Soria J, Vallejo J, Castellano M, Martínez-Lillo J, Pardo E, Cano J, Castro I, Lloret F, Ruiz-García R, Julve M. Molecular magnetism, quo vadis?: A historical perspective from a coordination chemist viewpoint. Coordination Chemistry Reviews, 2017, 339: 17–103 https://doi.org/10.1016/j.ccr.2017.03.004
3
Miller J S. Magnetically ordered molecule-based materials. Chemical Society Reviews, 2011, 40(6): 3266–3296 https://doi.org/10.1039/c0cs00166j
4
Sieklucka B, Pinkowicz D. Molecular Magnetic Materials.Weinheim: Wiley-VCH Verlag GmbH & Co. KGaA, 2017, 1–483
5
Gaspar A B, Weber B. Spin Crossover Phenomenon in Coordination Compounds. In: Molecular Magnetic Materials. Weinheim: Wiley-VCH Verlag GmbH & Co. KGaA, 2017, 231–252
6
Halcrow M A. Spin-Crossover Materials. Chichester: John Wiley & Sons Ltd, 2013, 1–546
7
Feltham H L, Barltrop A S, Brooker S. Spin crossover in iron(II) complexes of 3,4,5-tri-substituted-1,2,4-triazole (Rdpt), 3,5-di-substituted-1,2,4-triazolate (dpt -), and related ligands. Coordination Chemistry Reviews, 2017, 344: 26–53 https://doi.org/10.1016/j.ccr.2016.10.006
8
Ni Z P, Liu J L, Hoque M N, Liu W, Li J Y, Chen Y C, Tong M L. Recent advances in guest effects on spin-crossover behavior in Hofmann-type metal-organic frameworks. Coordination Chemistry Reviews, 2017, 335: 28–43 https://doi.org/10.1016/j.ccr.2016.12.002
9
Otsubo K, Haraguchi T, Kitagawa H. Nanoscale crystalline architectures of Hofmann-type metal-organic frameworks. Coordination Chemistry Reviews, 2017, 346: 123–138 https://doi.org/10.1016/j.ccr.2017.03.022
10
Senthil Kumar K, Ruben M. Emerging trends in spin crossover (SCO) based functional materials and devices. Coordination Chemistry Reviews, 2017, 346: 176–205 https://doi.org/10.1016/j.ccr.2017.03.024
11
Harding D J, Harding P, Phonsri W. Spin crossover in iron(III) complexes. Coordination Chemistry Reviews, 2016, 313: 38–61 https://doi.org/10.1016/j.ccr.2016.01.006
12
Brooker S. Spin crossover with thermal hysteresis: Practicalities and lessons learnt. Chemical Society Reviews, 2015, 44(10): 2880–2892 https://doi.org/10.1039/C4CS00376D
13
Gütlich P, Gaspar A B, Garcia Y. Spin state switching in iron coordination compounds. Beilstein Journal of Organic Chemistry, 2013, 9: 342–391 https://doi.org/10.3762/bjoc.9.39
14
Jureschi C-M, Linares J, Boulmaali A, Dahoo P R, Rotaru A, Garcia Y.Pressure and temperature sensors using two spin crossover materials. Sensors, 2016, 16: 187/1–187/9
15
Gütlich P, Goodwin H. Spin Crossover in Transition Metal Compounds I–III. Heidelberg: Springer, 2004, 1–294
16
Boillot M L, Weber B. Mononuclear ferrous and ferric complexes. Comptes Rendus. Chimie, 2018 (Online). doi: 10.1016/j.crci.2018.01.006
17
Weber B, Bauer W, Obel J. An iron(II) spin-crossover complex with a 70 K wide thermal hysteresis loop. Angewandte Chemie International Edition, 2008, 47(52): 10098–10101 https://doi.org/10.1002/anie.200802806
18
Levchenko G G, Bukin G V, Gaspar A B, Real J A. The pressure-induced spin transition in the Fe(phen)2(NCS)2 model compound. Russian Journal of Physical Chemistry A, 2009, 83(6): 951–954 https://doi.org/10.1134/S0036024409060144
19
Nowak R, Prasetyanto E A, de Cola L, Bojer B, Siegel R, Senker J, Rössler E, Weber B. Proton-driven coordination-induced spin state switch (PD-CISSS) of iron(II) complexes. Chemical Communications, 2017, 53(5): 971–974 https://doi.org/10.1039/C6CC08618G
20
Baldé C, Bauer W, Kaps E, Neville S, Desplanches C, Chastanet G, Weber B, Létard J F. Light-induced excited spin-state properties in 1D iron(II) chain compounds. European Journal of Inorganic Chemistry, 2013, 2013: 2744–2750
Luo Y H, Liu Q L, Yang L J, Sun Y, Wang J W, You C Q, Sun B W. Magnetic observation of above room-temperature spin transition in vesicular nano-spheres. Journal of Materials Chemistry C: Materials for Optical and Electronic Devices, 2016, 4(34): 8061–8069 https://doi.org/10.1039/C6TC02796B
23
Romero-Morcillo T, Seredyuk M, Munoz M C, Real J A. Meltable spin transition molecular materials with tunable Tc and hysteresis loop width. Angewandte Chemie International Edition, 2015, 54(49): 14777–14781 https://doi.org/10.1002/anie.201507620
24
Gandolfi C, Morgan G G, Albrecht M. A magnetic iron(III) switch with controlled and adjustable thermal response for solution processing. Dalton Transactions, 2012, 41(13): 3726–3730 https://doi.org/10.1039/c2dt12037b
25
Garcia Y, Su B-L, Komatsu Y, Kato K, Yamamoto Y, Kamihata H, Lee Y H, Fuyuhiro A, Kawata S, Hayami S.Spin-crossover behaviors based on intermolecular interactions for cobalt(II) complexes with long alkyl chains. European Journal of Inorganic Chemistry, 2012, 2012: 2769–2775
26
Schlamp S, Weber B, Naik A D, Garcia Y. Cooperative spin transition in a lipid layer like system. Chemical Communications, 2011, 47(25): 7152–7154 https://doi.org/10.1039/c1cc12162f
27
Schlamp S, Thoma P, Weber B. Influence of the alkyl chain length on the self-assembly of amphiphilic iron complexes: An analysis of X-ray structures. Chemistry, 2014, 20(21): 6462–6473 https://doi.org/10.1002/chem.201304653
28
Bodenthin Y, Schwarz G, Tomkowicz Z, Lommel M, Geue T, Haase W, Möhwald H, Pietsch U, Kurth D G. Spin-crossover phenomena in extended multi-component metallo-supramolecular assemblies. Coordination Chemistry Reviews, 2009, 253(19–20): 2414–2422 https://doi.org/10.1016/j.ccr.2008.10.019
29
Gaspar A B, Seredyuk M, Gütlich P. Spin crossover in metallomesogens. Coordination Chemistry Reviews, 2009, 253(19–20): 2399–2413 https://doi.org/10.1016/j.ccr.2008.11.016
30
Zein S, Borshch S A. Energetics of binuclear spin transition complexes. Journal of the American Chemical Society, 2005, 127(46): 16197–16201 https://doi.org/10.1021/ja054282k
31
Lochenie C, Schötz K, Panzer F, Kurz H, Maier B, Puchtler F, Agarwal S, Köhler A, Weber B. Spin-crossover iron(II) coordination polymer with fluorescent properties: Correlation between emission properties and spin state. Journal of the American Chemical Society, 2018, 140(2): 700–709 https://doi.org/10.1021/jacs.7b10571
32
Kurz H, Lochenie C, Wagner K G, Schneider S, Karg M, Weber B. Synthesis and optical properties of phenanthroline-derived Schiff base-like dinuclear Ru(II)-Ni(II) complexes. Chemistry, 2018, 24(20): 5100–5111 https://doi.org/10.1002/chem.201704632
33
Schäfer B, Bauer T, Faus I, Wolny J A, Dahms F, Fuhr O, Lebedkin S, Wille H C, Schlage K, Chevalier K, et al.. A luminescent Pt2Fe spin crossover complex. Dalton Transactions, 2017, 46(7): 2289–2302 https://doi.org/10.1039/C6DT04360G
34
Shepherd H J, Quintero C M, Molnár G, Salmon L, Bousseksou A. Luminescent Spin-Crossover Materials. In: Spin-Crossover Materials. Chichester: John Wiley & Sons Ltd, 2013, 347–373
35
Hasegawa M, Renz F, Hara T, Kikuchi Y, Fukuda Y, Okubo J, Hoshi T, Linert W. Fluorescence spectra of Fe(II) spin crossover complexes with 2,6-bis(benzimidazole-2′-yl)pyridine. Chemical Physics, 2002, 277(1): 21–30 https://doi.org/10.1016/S0301-0104(01)00706-6
36
Faulmann C, Jacob K, Dorbes S, Lampert S, Malfant I, Doublet M L, Valade L, Real J A. Electrical conductivity and spin crossover: A new achievement with a metal bis dithiolene complex. Inorganic Chemistry, 2007, 46(21): 8548–8559 https://doi.org/10.1021/ic062461c
37
Dorbes S, Valade L, Real J A, Faulmann C. [Fe(sal2-trien)][Ni(dmit)2]: Towards switchable spin crossover molecular conductors. Chemical Communications, 2005, (1): 69–71 https://doi.org/10.1039/b412182a
38
Chen Y C, Meng Y, Ni Z P, Tong M L. Synergistic electrical bistability in a conductive spin crossover heterostructure. Journal of Materials Chemistry C: Materials for Optical and Electronic Devices, 2015, 3(5): 945–949 https://doi.org/10.1039/C4TC02580F
39
Ohkoshi S I, Imoto K, Tsunobuchi Y, Takano S, Tokoro H. Light-induced spin-crossover magnet. Nature Chemistry, 2011, 3(7): 564–569 https://doi.org/10.1038/nchem.1067
40
Suleimanov I, Kraieva O, Sánchez Costa J, Fritsky I O, Molnár G, Salmon L, Bousseksou A. Electronic communication between fluorescent pyrene excimers and spin crossover complexes in nanocomposite particles. Journal of Materials Chemistry C: Materials for Optical and Electronic Devices, 2015, 3(19): 5026–5032 https://doi.org/10.1039/C5TC00667H
41
Kraieva O, Suleimanov I, Molnár G, Salmon L, Bousseksou A. CdTe quantum dot fluorescence modulation by spin crossover. Magnetochemistry, 2016, 2(1): 11 https://doi.org/10.3390/magnetochemistry2010011
42
Quintero C M, Gural’skiy I A, Salmon L, Molnar G, Bergaud C, Bousseksou A. Soft lithographic patterning of spin crossover complexes. Part 1: Fluorescent detection of the spin transition in single nano-objects. Journal of Materials Chemistry, 2012, 22(9): 3745–3751 https://doi.org/10.1039/c2jm15662h
43
Weber B. Synthesis of coordination polymer nanoparticles using self-assembled block copolymers as template. Chemistry, 2017, 23(72): 18093–18100 https://doi.org/10.1002/chem.201703280
44
Klimm O, Göbel C, Rosenfeldt S, Puchtler F, Miyajima N, Marquardt K, Drechsler M, Breu J, Förster S, Weber B. Synthesis of Fe(L)(bipy)n spin crossover nanoparticles using blockcopolymer micelles. Nanoscale, 2016, 8(45): 19058–19065 https://doi.org/10.1039/C6NR06330F
45
Fitzpatrick A J, O’Connor H M, Morgan G G. A room temperature spin crossover ionic liquid. Dalton Transactions, 2015, 44(48): 20839–20842 https://doi.org/10.1039/C5DT04264J
46
Okuhata M, Funasako Y, Takahashi K, Mochida T. A spin-crossover ionic liquid from the cationic iron(III) Schiff base complex. Chemical Communications, 2013, 49(69): 7662–7664 https://doi.org/10.1039/c3cc44199g
47
Liu X, Manzur C, Novoa N, Celedón S, Carrillo D, Hamon J R. Multidentate unsymmetrically-substituted Schiff bases and their metal complexes: Synthesis, functional materials properties, and applications to catalysis. Coordination Chemistry Reviews, 2018, 357: 144–172 https://doi.org/10.1016/j.ccr.2017.11.030
48
Altomare A, Burla M C, Camalli M, Cascarano G L, Giacovazzo C, Guagliardi A, Moliterni A G G, Polidori G, Spagna R. SIR97: A new tool for crystal structure determination and refinement. Journal of Applied Crystallography, 1999, 32(1): 115–119 https://doi.org/10.1107/S0021889898007717
49
Sheldrick G M. A short history of SHELX. Acta Crystallographica. Section A, Foundations of Crystallography, 2008, 64(1): 112–122 https://doi.org/10.1107/S0108767307043930
50
Farrugia L. ORTEP-3 for Windows—a version of ORTEP-III with a Graphical User Interface (GUI). Journal of Applied Crystallography, 1997, 30(5): 565 https://doi.org/10.1107/S0021889897003117
51
Johnson C K, Burnett M N. ORTEP-III. Oak-Ridge: Oak-Ridge National Laboratory, 1996
52
Keller E. Schakal-99. Freiburg: University of Freiburg, 1999
53
Kahn O. Molecular Magnetism. New York: VCH, 1993, 1–380
54
Becker H G O. Organikum, 19th ed. Berlin: Johann Ambrosius Barth, 1993, 1–786
55
Jäger E G. “Bioinspired” metal complexes of macrocyclic [N42-] and open chain [N2O22-] Schiff base ligands—a link between porphyrins and salicylaldimines. In: Chemistry At The Beginning of The Third Millennium: Molecular Design, Supramolecules, Nanotechnology, And Beyond. Berlin: Springer, 2000, 103–138
56
Jäger E G. Koordinierte und freie Estergruppen in stabilen Metallchelaten. Zeitschrift fur Anorganische und Allgemeine Chemie, 1967, 349: 139–150 https://doi.org/10.1002/zaac.19673490305
Weber B, Betz R, Bauer W, Schlamp S. Crystal structure of iron(II) acetate. Zeitschrift fur Anorganische und Allgemeine Chemie, 2011, 637(1): 102–107 https://doi.org/10.1002/zaac.201000274
59
Holleman A F, Wiberg E, Wiberg N. Lehrbuch der anorganischen Chemie, 101st ed. Berlin: de Gruyter, 1995, 1–2149
60
Weber B, Jäger E-G. Structure and magnetic properties of iron(II/III) complexes with N2O22- coordinating Schiff base like ligands. European Journal of Inorganic Chemistry, 2009, 2009: 465–477
61
Bauer W, Ossiander T, Weber B.A promising new Schiff base-like ligand for the synthesis of octahedral iron(II) spin crossover complexes. Zeitschrift für Naturforschung B, 2010, 2010: 323–328
Dankhoff K, Weber B. Novel Cu(II) complexes with NNO-Schiff base-like ligands—structures and magnetic properties. CrystEngComm, 2018, 20(6): 818–828 https://doi.org/10.1039/C7CE02007D
64
Weber B, Kaps E, Obel J, Bauer W. Synthesis and magnetic properties of new octahedral iron(II) complexes. Zeitschrift fur Anorganische und Allgemeine Chemie, 2008, 634(8): 1421–1426 https://doi.org/10.1002/zaac.200800132
65
Weber B, Obel J, Henner-Vasquez D, Bauer W.Two new iron(II) spin-crossover complexes with N4O2 coordination sphere and spin transition around room temperature. European Journal of Inorganic Chemistry, 2009, 2009: 5527–5534
66
Pfaffeneder T M, Thallmair S, Bauer W, Weber B. Complete and incomplete spin transitions in 1D chain iron(II) compounds. New Journal of Chemistry, 2011, 35(3): 691–700 https://doi.org/10.1039/C0NJ00750A
67
Bauer W, Pfaffeneder T, Achterhold K, Weber B. Complete two-step spin-transition in a 1D chain iron(II) complex with a 110-K wide intermediate plateau. European Journal of Inorganic Chemistry, 2011, 2011: 3183–3192
68
Schlamp S, Thoma P, Weber B. New octahedral, head-tail iron(II) complexes with spin crossover properties. European Journal of Inorganic Chemistry, 2012, 2012: 2759–2768
69
Weber B. Spin crossover complexes with N4O2 coordination sphere—the influence of covalent linkers on cooperative interactions. Coordination Chemistry Reviews, 2009, 253(19–20): 2432–2449 https://doi.org/10.1016/j.ccr.2008.10.002
70
Göbel C, Klimm O, Puchtler F, Rosenfeldt S, Förster S, Weber B. Synthesis of [Fe(Leq)(Lax)]n coordination polymer nanoparticles using blockcopolymer micelles. Beilstein Journal of Nanotechnology, 2017, 8: 1318–1327 https://doi.org/10.3762/bjnano.8.133
71
Nowak R, Bauer W, Ossiander T, Weber B. Slow self-assembly favours hysteresis above room temperature for an iron(II) 1D-chain spin-crossover complex. European Journal of Inorganic Chemistry, 2013, 2013: 975–983
72
Weber B, Kaps E S, Desplanches C, Létard J-F. Quenching the hysteresis in single crystals of a 1D chain iron(II) spin crossover complex. European Journal of Inorganic Chemistry, 2008, 2008: 2963–2966