160325-19-9Relevant academic research and scientific papers
Cyclopentadienyldicarbonyliron halides as electrophiles: Reactions of (η5-C5H5)Fe(CO)2I with MeLi in the presence of monophosphines and diphosphines
Luh, Lung-Shiang,Eke, Uche B.,Liu, Ling-Kang
, p. 440 - 447 (2008/10/08)
Treatment of equimolar amounts of (η5-C5H5)Fe(CO)2I and PR3 in THF at -78°C with slightly more than 1 molar equiv of MeLi produces mainly (η4-MeC5H5)Fe(CO)2(PR 3) (1-4) for PR3 = PPh3, PMePh2, PMe2Ph, PMe3, the yields increasing in the order PMe3 2 2Ph 3, parallel to the decreasing order of the σ-donating tendency and increasing cone angle. In the presence of Ph2PCH2PPh2 (=dppm) the reaction yields the unidentate complex (η4-MeC5H5)Fe(CO)2(η 1-dppm) (5). In the presence of Ph2P(CH2)nPPh2 (n = 2 (dppe), 3 (dppp), 4 (dppb)) the reaction yields the respective bridging [(η4-MeC5H5)Fe(CO) 2](μ,η1:η1-Ph2P(CH 2)nPPh2)[(η4-MeC 5H5)Fe(CO)2] complexes 6-8. Both complexes 2 and 6 have been investigated by X-ray structure analysis. The results indicate that the Me group is exo to the cyclopentadiene ring. The coordination geometry of Fe may be described as that of a distorted square pyramid with one CO placed at the apical position, phosphine in the basal plane trans to one of the double bonds, and the second CO ligand trans to the second double bond. A similar reaction of (η5-C5H5)Fe(CO)2I with n-BuLi at -78°C in the presence of dppe results in (η4-BuC5H5)Fe(CO) 2(μ,η1:η1-dppe)(η 4-BuC5H5)Fe(CO)2 (9), (η4-BuC5H5)Fe(CO) 2-(μ,η1:η1-dppe)(η 5-C5H5)Fe(CO)C(O)Bu (10), and (η5-C5H5)Fe(CO)C(O)Bu(μ,η 1:η1-dppe)(η5-C5H 5)Fe(CO)C(O)Bu (11) in 55%, 18%, and 1% yields, respectively.
