Synthesis, structure, and redox properties of the sulfide bridged tetranuclear cluster complex [(Ph3P)(2)N][Fe-3(CO)(9){mu(3)-SFeCp(CO)(2)}]

Reaction of [CpFe(CO)(2)THF]BF4 with [(Ph3P)(2)](2)[Fe-3(CO)(9)(mu(3)-S)] ( 1) produces the new cluster [(Ph3P)(2)N][Fe-3(CO)(9){mu(3)-SFeCp(CO)(2)}] ( 2), which consists of a Fe-3(CO)(9)S fragment coordinated to the iron atom of CpFe(CO)(2). Compound 2 was characterized by H-1 and C-13 NMR, mass spec troscopy, elemental analysis, cyclic voltammetry, and single crystal X-ray structure determination. Compound 2 undergoes a quasi reversible oxidation at 0.19 V versus Ag\AgCl. Chemical oxidation of 2 by tropylium produces the known cluster Fe-3(CO)(9)(mu(3)-S)(2). Thermolysis of 2 yields the known c ompounds [CpFe(CO)(2)](2), [(Ph3P)(2)N](2)[Fe-3(CO)(9)(mu(3)-S)], and [(Ph3 P)(2)N](2)[Fe-3(CO)(14)(mu(3)-S)(2)] (3), which were identified by IR and m ass spectrometry. (C) 1999 Elsevier Science S.A. All rights reserved.