Abstract
To explore the structural transformation of cyclopentadienyl ruthenium (CpRu) complexes in response to external stimuli, the reaction of [RuCp(MeCN)3][X] (X = PF6, (FSO2)2N [= FSA]) and tris(alkylthio)benzenes (1,3,5-C6H3(SR)3; L1: R = Pr, L2: R = Me) was investigated, and the crystal structures and thermal properties of the products were examined. The reaction produced the sandwich complexes [RuCpLn][X] or dinuclear complexes [Ru2Cp2(μ-Ln)2(CH3CN)m][X]2 (X = PF6, FSA) depending on the reaction conditions. The sandwich complex [RuCpL1][FSA] was an ionic liquid. The solids of dinuclear complexes transformed into the thermodynamically stable sandwich complexes upon heating accompanied by acetonitrile loss. This change resulted in a transformation from crystal to ionic liquid for complexes with the FSA anion. UV irradiation of the sandwich complex [RuCpL1][PF6] in methanol produced the dinuclear complex [Ru2Cp2(μ-L1)2L12][PF6]2. The complex transformed into the sandwich complex upon heating.
Highlights
Many cyclopentadienyl ruthenium (CpRu) complexes have been synthesized to date because of the interest in their chemical reactivities and catalytic activities.[1−15] They are used for the construction of various supramolecular assemblies.[16−18] A versatile precursor for their production is the triacetonitrile complex [RuCp(MeCN)3]+,9−13 which produces cationic sandwich-type Ru complexes upon reaction with arene ligands.[13−15]
Ionic liquids are salts with melting points below 100 °C,23,24 and we have synthesized a variety of organometallic ionic liquids containing cationic sandwich complexes.[19−22] In particular, ionic liquids with the formula [RuCp(arene)][X] (X = fluorinated anion) have been prepared using the reaction of [RuCp(MeCN)3]+ with arene ligands.[25−28] As part of this investigation, we previously found that the reaction with orthosubstituted benzenes afforded either sandwich-type or chelate complexes depending on the reaction conditions (Figure 1), and their interconversion in solution was possible upon application of light and heat.[29]
The reaction of the triacetonitrile CpRu complex [RuCp(MeCN)3]+ with 1,3,5-tris(alkylthio)benzenes produced either sandwich-type complexes or dinuclear complexes depending on reaction conditions
Summary
The reaction with 1,3,5-C6H3(SR)[3] ligands (L1: R = Pr; L2: R = Me) produced sandwich-type or dinuclear complexes depending on the reaction condition (Figure 2). A solution of [RuCp(MeCN)3][PF6] and L1 or L2 in 1,2-dichloroethane was heated at 90 °C for 16 h to produce the sandwich-type complexes [1a][PF6] and [1b][PF6] in 83 and 76% yields, respectively (Figure 2, top), as pale yellow crystals. The reaction of [RuCp(MeCN)3][PF6] and the ligands in acetone at room temperature produced orange crystals of the acetonitrile-coordinated dinuclear complexes
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
