Publication
Structural Variety of Iron Carbonyl Clusters Featuring Ferrocenylphosphines
Publisher:
Wiley
Date:
13-05-2021
DOI:
10.1002/EJIC.202100097
Abstract: The reaction chemistry of Fe 2 (CO) 9 ( 10 ) with ferrocenenyl dichlorophosphines of different substitution is discussed. Single FcPCl 2 , ( 5 ) as well as 1,1’‐ ( 6 ) and 1,2‐ ( 9 ) difunctionalized phosphines were used, of which 6 and 9 , were prepared in a novel straightforward synthetic process. Substrate 5 gave butterfly‐shaped Fe 2 (CO) 6 (μ 2 ‐Cl)(μ 2 ‐PFcCl) and Fe 2 (CO) 6 (μ 2 ‐PFcR 1 )(μ 2 ‐PFcR 2 ) (R 1 , R 2 =Cl, H). In addition, nido ‐Fe 3 (CO) 10 (μ 3 ‐PFc) and nido ‐Fe 3 (CO) 9 (μ 3 ‐PFc) 2 were obtained. 1,1’‐Functionalized 6 bridges both ends of the Fe 2 (CO) 6 entity. Therein, the so far smallest non‐binding P⋅⋅⋅P distance (2.7674(12) Å) between both 1,1’‐substituents is observed. Additionally, an ‘organometallic octabisvalene ’, containing two [2]ferrocenophane entities was obtained. The eight‐membered cyclic structure is twisted by 35.31(9)° regarding their ferrocenyl axis. Usage of 1,2‐(PCl 2 ) 2 functionalized 9 produced two isomers of a P−P connected dimer, which coordinates towards two independent Fe 2 (CO) 6 fragments in a novel μ,μ’,κ 8 or bis(μ,κ 4 ) fashion, resulting in a meso isomer with a planar core, and a racem mixture, possessing a pocket‐type structure. The latter shows the so far shortest observed P⋅⋅⋅P distance of 2.950(7) Å between two ortho P atoms of a ferrocenyl backbone. The results confirm that the geometric properties of ferrocenyls featuring 1,1’‐ and 1,2‐substitution patterns are not comparable with phenyl‐based analogues. X‐ray single crystal solid state structures, and DFT calculations were carried out.