New insights into progressive ligand replacement from [Ru₂Cl(O₂CCH₃)₄]: synthetic strategies and variation in redox potentials and paramagnetic shifts

Abstract

The complete series of [Ru2Cl(Dp-FPhF)4-x(O2CCH3)x] (x = 1 – 4; Dp-FPhF- = N,N’-bis(4-fluorophenyl)formamidinate) compounds, has been prepared and characterized by a multi-technique aproach, including single crystal X-ray diffraction. A careful...

Effect of Equatorial Ligand Substitution on the Reactivity with Proteins of Paddlewheel Diruthenium Complexes: Structural Studies

“…Here, we investigate interaction of the monosubstituted diruthenium compound [Ru 2 Cl­(D- p -FPhF)­(O 2 CCH 3 ) 3 ], where D- p -FPhF = N , N ′-bis­(4-fluorophenyl)­formamidinate (Figure ), with HEWL under four different experimental conditions. [Ru 2 Cl­(L–L)­(O 2 CCH 3 ) 3 ] compounds are soluble in H 2 O and are expected to be more stable than [Ru 2 Cl­(O 2 CCH 3 ) 4 ] according to the previous results …”

“…The results are compared with those obtained when proteins react with [Ru 2 Cl­(O 2 CCH 3 ) 4 ] and various dirhodium compounds. − The stability of [Ru 2 Cl­(D- p -FPhF)­(O 2 CCH 3 ) 3 ] was first studied in solution by UV–vis absorption spectroscopy (Figure ). The spectrum in dichloromethane showed only one transition band around 480 nm . However, in H 2 O, the electronic spectrum shows bands in the UV (243 and 338 nm) and visible (∼420 and 520 nm) regions.…”

“…Recently, it has been suggested that the use of bulky equatorial substituents on the diruthenium core may constitute an approach to increase the selectivity of diruthenium complexes toward anticancer targets. , Many diruthenium complexes of the type [Ru 2 Cl­(L–L) 4 ] (L–L = O,N donors, , N,N′ -donors , or other O,O′ -donors , ) have been synthesized. However, intermediate substitution species [Ru 2 Cl­(L–L) x (O 2 CCH 3 ) 4– x ] ( x = 1–3) are quite scarce. ,− These molecules show variations in the stability, solubility, redox potential, and paramagnetic behavior compared to [Ru 2 Cl­(O 2 CCH 3 ) 4 ] and to their fully substituted species.…”

Diruthenium complexes as pH-responsive delivery systems: a quantitative assessment

“…64,65 The coordination of ligands at both axial positions is possible, 54 but less likely with three formamidinate ligands. 40…”

“…39 We used, the auxins indole-3-acetate (IAA), 2,4-dichlorophenoxyacetate (2,4-D), and 1-naphthaleneacetate (NAA), to prepare [Ru 2 Cl(μ-DPhF) 3 (μ-IAA)] ( RuIAA ), [Ru 2 Cl(μ-DPhF) 3 (μ-2,4-D)] ( Ru2,4-D ) and [Ru 2 Cl(μ-DPhF) 3 (μ-NAA)] ( RuNAA ) (DPhF = N , N ′-diphenylformamidinate). The presence of three formamidinate ligands confers great stability to the diruthenium core, 40,41 which is a great advantage over the tetracarboxylato complexes usually employed. This stability 39 avoids the decomposition of the molecule prior to the auxin release, which is time-dependent and only occurs rapidly under slightly acidic pH conditions (pH = 6.5).…”