Triphenylguanidine‐Promoted ortho‐Metalation Reaction in a Triply Bonded Dirhenium System – Spectroscopic, Structural, and Computational Studies. Issue 10 (18th February 2015)

• Record Type: Journal Article
• Authors: Mallick, Suman; Ghosh, Mrinal Kanti; Chattopadhyay, Swarup
• Is Part Of: European journal of inorganic chemistry. Issue 10(2015)
• Page Start: 1759
• Page End: 1765
• Publication Date: 2015-02-18
• Subjects: Rhenium -- N ligands -- Redox chemistry -- Metalation -- Density functional calculations; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201403207
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: Triphenylguanidine‐promoted ortho ‐metalation reactions have been observed in reactions between the triply bonded dirhenium(II) complex Re2 Cl4 (μ‐Ph2 PCH2 PPh2 )2 (1 ) and different para ‐substituted triphenylguanidine ligands (HTPG R ) in ethanol under reflux. The products are of the type Re2 Cl2 (μ‐dppm)(μ‐dppm°)(TPG R ) [2 (R), dppm = Ph2 PCH2 PPh2, μ‐dppm° represents the ortho ‐metalated dppm ligand and R = H, 2 (H); Me, 2 (Me), and OMe, 2 (OMe)]. These are the first examples of ortho ‐metalated dirhenium complexes with bridging dppm ligands. These complexes have very similar spectral (UV/Vis, IR, and NMR) and electrochemical properties, which are also reported. The solid‐state structure of2 (H) has been established by single‐crystal X‐ray diffraction [Re–Re distance 2.2741(6) Å]. In the solid state, the molecules are linked by π··· π and C–H··· π intermolecular interactions and form infinite supramolecular chains. Anion··· π interactions have also been revealed in the solid state. The electronic structures of the complexes are also scrutinized by density functional theory (DFT) calculations. Abstract : A series of ortho ‐metalated dirhenium complexes are prepared by reacting Re2 Cl4 (μ‐Ph2 PCH2 PPh2 )2 with different para ‐substituted triphenylguanidine ligands (HTPG R, R = H, Me, OMe) and characterized by different spectroscopic techniques and by X‐ray crystallography. The complexes have similar spectral and electrochemical properties, which are consistent with the results of a theoretical study.