Syntheses, spectroscopic characterization and electrochemical properties of organometallic crown ethers containing tetrahedral W2Fe(μ3-S) cluster cores [W2Fe(μ3-S)(CO)7][η5-C5H4CH2(CH2OCH2)nCH2C5H4-η5] (n=1–3). Crystal structures of [W2Fe(μ3-S)(CO)7][η5-C

The self-assembly cyclization reactions of the ether chain-bridged dicyclopentadienyl W/Na salts Na2[{W(CO)3}2{η5-C5H4CH2(CH2OCH2)nCH2C5H4-η5}] (Ia–c, n=1–3) with the same chain-bridged dicyclopentadienyl double clusters [WCoFe(μ3-S)(CO)8]2[η5-C5H4CH2(CH2OCH2)nCH2C5H4-η5] (IIa–c, n=1–3) have been shown to give organometallic crown ethers [W2Fe(μ3-S)(CO)7][η5-C5H4CH2 (CH2OCH2)nCH2C5H4-η5] (IIIa–c, n=1–3). While structures of these new W2Fe(μ3-S) cluster crown ethers were fully characterized by elemental analyses, IR, 1H-NMR and FAB-MS spectroscopies, those of IIIb,c were unambiguously confirmed by X-ray diffraction techniques. In the study of possible pathway for the formation of IIIa–c, the new cluster crown ether IIIc and its known Mo analog [Mo2Fe(μ3-S)(CO)7][η5-C5H4CH2(CH2OCH2)3CH2C5H4-η5] (IV) were also found to be formed through self-assembly cyclization reaction of the W/Na salt Na2[{W(CO)3}2{η5-C5H4CH2(CH2OCH2)3CH2C5H4-η5}] and the corresponding Mo-containing double cluster [MoCoFe(μ3-S)(CO)8]2[η5-C5H4CH2(CH2OCH2)3CH2C5H4-η5]. In addition, the electrochemical properties of IIIa–c have been studied by cyclic voltammetric techniques.