Exploring the Optimal Synthetic Pathways towards µ‐Carbido Diruthenium(IV) Bisphthalocyaninates

• Published in: European journal of inorganic chemistry 2019-04, Vol.2019 (14), p.1923-1931
• Main Authors: Kroitor, Andrey P., Martynov, Alexander G., Gorbunova, Yulia G., Tsivadze, Aslan Yu, Sorokin, Alexander B.
• Format: Article
• Language: English
• Subjects: Carbido complexes; Carbonyl complexes; Catalysis; Chemical Sciences; Chloroform; Dimerization; Dimers; Environment and Society; Environmental Sciences; Inorganic chemistry; Phthalocyanines; Refluxing; Ruthenium; Sandwich complexes; Substitutes
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.201900029

Series of substituted µ‐carbido diruthenium(IV) bisphthalocyaninates [Pc*Ru]2(µ‐C) [where Pc* = tetra‐tert‐butyl‐, octa‐n‐butoxy‐, tetra‐15‐crown‐5‐ and hexa‐n‐butoxy‐mono‐(15‐crown‐5)‐substituted ligands] were synthesized using two alternative approaches – (i) direct metalation of phthalocyanines with Ru3(CO)12 in refluxing o‐dichlorobenzene where [Pc*Ru]2(µ‐C) are formed as by‐products together with monomeric complexes [Pc*Ru](CO) and (ii) dimerization of [Pc*Ru](CO) by dichlorocarbene generated in situ from chloroform and bases (KOH or NMe4OH), which affords target complexes in high yield. Application of the appropriate base – NMe4OH was found to be crucial in the case of synthesis of crown‐substituted µ‐carbido dimers. Reaction of Ru3(CO)12 with the phthalocyanine bearing bulky mesityloxy‐groups yielded solely monomeric complex which could not be dimerized under any studied conditions. Therefore, the influence of nature of peripheral substituents in phthalocyanines on their reactivity in metalation and dimerization reactions was revealed. Series of substituted µ‐carbido diruthenium(IV) bisphthalocyaninates [Pc*Ru]2(µ‐C) (where Pc* = tert‐butyl, n‐butoxy‐ and crown‐substituted ligands) were synthesized either by direct metalation of phthalocyanines or via dimerization of [Pc*Ru](CO) by dichlorocarbene generated in situ from chloroform and basic reagents.