Group 9 bimetallic carbonyl permethylpentalene complexesElectronic supplementary information (ESI) available: Crystallographic information files for structures 1-3 and calculated Cartesian coordinates. CCDC 1417859-1417861. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5dt03747f

• Main Authors: Chadwick, F. Mark, Ashley, Andrew E, Cooper, Robert T, Bennett, Luke A, Green, Jennifer C, O'Hare, Dermot M
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c5dt03747f

We describe the synthesis, structure and bonding of the first iridium and rhodium permethylpentalene complexes, syn -[M(CO) 2 ] 2 (μ:η 5 :η 5 -Pn*) (M = Rh, Ir). In fact, [Ir(CO) 2 ] 2 (μ:η 5 :η 5 -Pn*) is the first iridium pentalene complex. An interesting preference for the isolation of the sterically more demanding syn -isomer is observed and substantiated by DFT analysis. Upon photolysis, the rhodium analogue yields an unusual tetrameric species Rh 4 (CO) 6 (μ:η 3 :η 5 -Pn*) 2 with bridging carbonyls and Rh-Rh bonds, which has been characterised by single crystal X-ray diffraction and by solution NMR spectroscopy. We describe the synthesis, structure and bonding of the first iridium and rhodium permethylpentalene complexes, syn -[M(CO) 2 ] 2 (μ:η 5 :η 5 -Pn*) (M = Rh, Ir).