Remarkable thermal stability of light-induced Ru–ON linkage isomers in mixed salts of a ruthenium amine complex with a trans-ON–Ru–F coordinate

Abstract

The novel complexes with trans-ON–Ru–F coordinate exhibit the highest thermal stability of Ru–ON photoinduced isomers.

Ruthenium-nitrosyl complexes as NO-releasing molecules, potential anticancer drugs, and photoswitches based on linkage isomerism

“…On the other hand, significant progress has been made concerning the stability of the PLI, important for potential applications. In particular, a record high stability has been achieved by introducing F as a trans-to-NO ligand, and it could be shown that MS1 can be generated at room temperature with a lifetime of 120 -150 s. 48,137 The increase in stability for F-based complexes was predicted by theory 139 and has been further underlined by additional studies on a series of [RuF(NH 3 ) 4 NO] 2+ complexes with different counteranions 37,36,22 as well as on RuNOF complexes mixing pyridine and ammine equatorial ligands. 35 These high stabilities open the path to combining PLI with other properties, such as nonlinear optical response.…”

“…The most common synthetic routes to ruthenium nitrosyl complexes include: (a) the use of specific starting materials, which already contain the ruthenium nitrosyl moiety, via a variety of substitution reactions (NO 2 by Cl, 27 NH 3 , 28,29 pyridines, [29][30][31][32][33] pyrazine; 34 NO 3 by H 2 O, F; 35 OH by F; 22,36,37 Cl by pyridines, [38][39][40] tetradentate Schiff bases, 41,42 tetradentate 2-hydroxybenzamidobenzene derivatives, 43 bis-phosphine monoxide ligands; 44 H 2 O by Cl, 45 SO 4 ; 46 NH 3 by Cl 46 ) or metathesis reactions of Na + to Ba 2+ , 29 Ba 2+ to NH 4 + , 29 Cl − to ClO 4 − , 47 PF 6 − , 48 in solution and in the solid state; 45,46 (b) conversion of the coordinated nitro ligand into nitrosyl in acidic media (HCl, TFA, HFP 6 , HNO 3 ) reported for ruthenium triammine complex, 45 as well as for compounds with pyridine, bipyridine, terpyridine, phenanthroline, triazine, and indazole ligands (see references in Table 1); (c) direct reaction of ruthenium pyridine, bipyridine, terpyridine, porphyrin, corrole species (see Table 1) or ruthenium azole complexes 49 with NO via substitution reactions of labile monodentate ligands, e.g., Cl, [50][51][52][53][54] H 2 O, 55,56 DMSO...…”

“…18,19 Therefore, the investigation of these intermediates is of great interest. Moreover, these photoisomerization processes in the solid state have potential to be used for data storage, 20,21 and in the design of photochromic materials 22 or hologram gratings because of the difference in refractive index of ground and metastable states. 23 Another interest is the use of ruthenium nitrosyl complexes as building blocks for assembly of systems combining a photo-switchable unit with a paramagnetic moiety in the same crystal or compound.…”

Photoinduced linkage isomers in a model ruthenium nitrosyl complex: Identification and assignment of vibrational modes

“…The higher the barrier the more stable the linkage isomer, which is very often indicated in the form of a so-called decay temperature T d , defined as the temperature where the decay rate constant of the metastable linkage isomer is 0.001 s -1 [20]. This type of isomerism is characteristic for different metals, but the most prominent results and effects was observed in octahedrally coordinated ruthenium complexes with the general formula of L 5 Ru-NO, due to the much higher decay temperatures of metastable states compared to other central metal atoms [20][21][22][23][24][25]. Among other methods applied for the study of the different linkage modes, IR-spectroscopy is the most powerful and sensitive tool to detect the changes of the NO coordination, since especially the ν(NO) stretching vibration has a large amplitude due to a very strong derivative of the dipole moment [26][27][28][29][30].…”

The Ruthenium Nitrosyl Moiety in Clusters: Trinuclear Linear μ-Hydroxido Magnesium(II)-Diruthenium(II), μ3-Oxido Trinuclear Diiron(III)–Ruthenium(II), and Tetranuclear μ4-Oxido Trigallium(III)-Ruthenium(II) Complexes

“… 31 , 32 Light-induced Ru–NO bond dissociation in solution 33 may involve the formation of the intermediate metastable linkage isomers MS1 (Ru-ON) and MS2 (Ru-η 2 -NO). 34 − 37 These photoisomerization processes in the solid state have potential uses in data storage 38 − 40 and in the design of photochromic materials 41 or hologram gratings on the basis of the difference in refractive indexes between the ground and metastable states. 42 Another interest is the use of ruthenium nitrosyl complexes as building blocks for the assembly of systems combining a photoswitchable unit with a paramagnetic moiety in the same crystal.…”