Novel Products from Reactions of Li[(.mu.-CO)(.mu.-RS)Fe2(CO)6] Salts with Ethoxyacetylene

Abstract

Reactions of Li[@-CO)@-RS)Fez(C0)6] salts with ethoxyacetylene followed by reaction of the anionic intermediate thus generated with acetyl or benzoyl chloride gave a n Fez(CO)s complex that contained the thiolate ligand as well as a novel resonance-stabilized bridging vinylcarbene ligand which incorporated the acetylene and an original CO ligand that may be written as -C(OEt)=CHC(OZCR')= -=C(OEt)CH-C(OzCR')-. The structure of the complex in which R = t-Bu and R1 = CH3 was determined by X-ray diffraction. Extended Huckel MO calculations for a model system, F~z(CO)~@-SH)@-C~H~), led to its description in terms of a n ideally delocalized C3 bridge coupled to the iron atoms of the @-HS)Fe~(co)6 unit by two strong a-bonds and by moderate mback-bonding. Protonation of the anionic intermediate with trifluoroacetic acid gave the a,/kinsaturated bridging acyl complexes @- (R = t-Bu, Et). The X-ray crystal structure of the complex in which R = t-Bu was determined. These complexes lost CO in THF solution at room temperature, giving Cu-EtOC=CHz)@-RS)Fez(C0)6. E~OC(=CHZ)C=O)@-RS)F~Z(CO)~

Syntheses, Structures and Photophysical Properties of Metal Carbonyl Clusters with Dansyl and Acridone Luminophores

“…In the IR spectra, the band patterns between the uncomplexed and complexed chromophores are similar. Coordination of the alkyne moiety to the metal core was confirmed by the close resemblance of the IR spectral pattern in the ν(CO) region of our complexes with those observed for the reported cobaltϪalkyne complexes, [25Ϫ28] [Fe 2 (CO) 6 (µ-SR)(µ-η 2 -RЈCϭCH 2 )] [18,29] and ЈM 3 (CO) 10 Ј cores (M ϭ Ru, Os) which coordinate an alkyne in a µ 3 -(η 2 -||) fashion. [21Ϫ24] The 1 H NMR spectra of the new complexes display resonances stemming from the coordinated dansyl or acridone group but the signals due to ϪCϵCH for I (ca.…”

“…These data agree with those reported for other [Fe 2 (CO) 6 (µ-SR)(µ-RЈC α ϭC β H 2 )] complexes and they are consistent with NMR spectroscopic data for other µ-vinyl systems as well. [18,29] The thiolate moieties in 3 and 4 display the expected singlet peak due to the tert-butyl group. These new compounds also gave satisfactory mass spectroscopic data and, in most cases, they showed the molecular ion peaks followed by the consecutive loss of carbonyl fragments.…”

Reactions of Iron Acyl Chalcogenide Clusters with Electrophiles: Reactivity Comparison and Theoretical Calculations

“…As summarized in Table 1, the average E-Fe and Fe-Fe bonds (E = S, Se) in clusters 4 and 6 were within the bonding ranges of the reported iron carbene complexes. The Fe-C carbene bond length in 4, 1.903(5) Å, is close to that in [Fe 3 (CO) 9 16 Moreover, the C carbene -C allyl and C-C bonds in the allylic fragment in 4 and 6 ranged from 1.408(6) to 1.466(7) Å and 1.31(1) to 1.46(1) Å, respectively, indicative of the double-bond character.…”

Iron Sulfido Derivatives of the Fullerenes C60 and C70

“…Evidence supporting the thermodynamic instability of C 60 S 2 Fe 2 (CO) 6 is provided by our inability to prepare these adducts by thermal routes including reactions of C 60 - with Fe 2 S 2 (CO) 6 and Fe 2 (S) 2 (CO) 6 2- with C 60 . Carbanions are known to cleave the S−S bond in this diiron reagent to give Fe 2 (SR)(S - )(CO) 6 which are susceptible to a second alkylation by electrophilic reagents (R‘X) to give Fe 2 (CO) 6 (SR)(SR‘) …”

“…The compound Fe 2 S 2 (CO) 6 was first synthesized by Hieber and Gruber and its structure was elucidated by Dahl's group which in many ways behaves like an organic disulfide . Of particular interest is the fact that upon irradiation, Fe 2 S 2 (CO) 6 adds to alkenes (eq 1) …”