Details

Autor(en) / Beteiligte

• Makhoul, Rim
• Groizard, Thomas
• Hamon, Paul
• Roisnel, Thierry
• Dorcet, Vincent
• Kahlal, Samia
• Halet, Jean‐François
• Hamon, Jean‐René
• Lapinte, Claude

Titel

1,4‐Diethynylbenzene‐Bridged [Cp(dppe)Fe] n+ Units: Effect of 2,5‐Ethynyl Groups on the Chemical and Electronic Properties

Ist Teil von

• European journal of inorganic chemistry, 2020-07, Vol.2020 (27), p.2624-2638

Erscheinungsjahr

2020

Quelle

Access via Wiley Online Library

Beschreibungen/Notizen

• The bis(ironvinylidene) complex [1,4‐{Cp*(dppe)Fe=C=CH} 2 ‐2,5‐(C≡CH) 2 ‐C 6 H 2 ](PF 6 ) 2 ( [2–2H](PF 6 ) 2 ) was prepared from 1,2,4,5‐tetraethynylbenzene and two equiv. of Cp*(dppe)FeCl in 87 % yield. The reaction is very selective and [2–2H](PF 6 ) 2 is the unique organoiron species to be formed. Deprotonation of [2–2H](PF 6 ) 2 provided the target complex 2 (66 % yield) and subsequent oxidation gave the monocationic and dicationic complexes 2(PF 6 ) and 2(PF 6 ) 2 . The new complexes were characterized by ESI‐mass spectrometry, IR, multinuclear NMR, ESR and Mössbauer spectroscopy, and XRD analyses on single crystals for [2–2H](PF 6 ) 2 and 2(PF 6 ) 2 . The magnetic properties of 2(PF 6 ) 2 were investigated by VT 1 H NMR. The data were analyzed with the support of quantum chemistry calculations. The terminal ethynyl groups on the aromatic ring of the bridge modify the population of the bridge‐oxidized state, weaken the electronic communication ( H ab ≈ 601 cm –1 ) and strengthen magnetic coupling interactions ( J = –530 cm –1 ) compared to the unsubstituted species ( H ab = 1700 cm –1 and J = –340 cm –1 , respectively).