Complexes of transition metal carbonyl clusters with tin(II) phthalocyanine in neutral and radical anion states: methods of synthesis, structures and properties

Nikita R Romanenko; Alexey V Kuzmin; Salavat S Khasanov; Maxim A Faraonov; Evgeniya I Yudanova; Yoshiaki Nakano; Akihiro Otsuka; Hideki Yamochi; Hiroshi Kitagawa; Dmitri V Konarev

doi:10.1039/d1dt04061h

Complexes of transition metal carbonyl clusters with tin(II) phthalocyanine in neutral and radical anion states: methods of synthesis, structures and properties

Dalton Trans. 2022 Feb 8;51(6):2226-2237. doi: 10.1039/d1dt04061h.

Authors

Affiliations

¹ Institute of Problems of Chemical Physics RAS, Chernogolovka, Moscow region, 142432 Russia. konarev3@yandex.ru.
² Institute of Solid State Physics RAS, Chernogolovka, Moscow region, 142432 Russia.
³ Division of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
⁴ Research Center for Low Temperature and Materials Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.

PMID: 35044409
DOI: 10.1039/d1dt04061h

Abstract

Coordination of tin(II) phthalocyanine to transition metal carbonyl clusters in neutral {Sn^II(Pc^2-)}⁰ or radical anion {Sn^II(Pc˙^3-)}^- states is reported. Direct interaction of Co₄(CO)₁₂ with {Sn^II(Pc^2-)}⁰ yields a crystalline complex {Co₄(CO)₁₁·Sn^II(Pc^2-)} (1). There is no charge transfer from the cluster to phthalocyanine in 1, which preserves the diamagnetic Pc^2- macrocycle. The Ru₃(CO)₁₂ cluster forms complexes with one or two equivalents of {Sn^II(Pc˙^3-)}^- to yield crystalline {Cryptand[2.2.2](Na⁺)}{Ru₃(CO)₁₁·Sn^II(Pc˙^3-)}^- (2) or {Cryptand[2.2.2](M⁺)}₂{Ru₃(CO)₁₀·[Sn^II(Pc˙^3-)]₂}^2-·4C₆H₄Cl₂ (3) (M⁺ is K or Cs). Paramagnetic {Sn^II(Pc˙^3-)}^- species in 2 are packed in π-stacking [{Sn^II(Pc˙^3-)}^-]₂ dimers, providing strong antiferromagnetic coupling of spins with exchange interaction J/k_B = -19 K. Reduction of Ru₃(CO)₁₂, Os₃(CO)₁₂ and Ir₄(CO)₁₂ clusters by decamethylchromocene (Cp*₂Cr) and subsequent oxidation of the reduced species by {Sn^IVCl₂(Pc^2-)}⁰ yield a series of complexes with high-spin Cp*₂Cr⁺ counter cations (S = 3/2): (Cp*₂Cr⁺){Ru₃(CO)₁₁·Sn^II(Pc˙^3-)}^-·C₆H₄Cl₂ (4), (Cp*₂Cr⁺){Os₃(CO)₁₀Cl·Sn^II(Pc˙^3-)}^-·C₆H₄Cl₂ (5) and (Cp*₂Cr⁺){Ir₄(CO)₁₁·Sn^II(Pc˙^3-)}₂^- (6). It is seen that reduced clusters are oxidized by Sn^IV, which is transferred to Sn^II, whereas the Pc^2- macrocycle is reduced to Pc˙^3-. In the case of Os₃(CO)₁₂, oxidation of the metal atom in the cluster is observed to be accompanied by the formation of Os₃(CO)₁₀Cl with one Os^I center. Rather weak magnetic coupling is observed between paramagnetic Cp*₂Cr⁺ and {Sn^II(Pc˙^3-)}^- species in 4, but this exchange interaction is enhanced in 5 owing to Os₃(CO)₁₀Cl clusters with paramagnetic Os^I (S = 1/2) also being involved in antiferromagnetic coupling of spins. The formation of {Sn^II(Pc˙^3-)}^- with radical trianion Pc˙^3- macrocycles in 2-5 is supported by the appearance of new absorption bands in the NIR spectra and essential N_meso-C bond alternation in Pc (for 3-5). On the whole, this work shows that both diamagnetic {Sn^II(Pc^2-)}⁰ and paramagnetic {Sn^II(Pc˙^3-)}^- ligands substitute carbonyl ligands in the transition metal carbonyl clusters, forming well-soluble paramagnetic solids absorbing light in the visible and NIR ranges.