PHOTOREACTION OF SILYLIRON(II) COMPLEX CP-ASTERISK-FE(CO)(2)SIME(3) (CP-ASTERISK=ETA(5)-C(5)ME(5)) IN THE PRESENCE OF P-TOLYLGERMANE

Photolysis of Cp()Fe(CO)(2)SiMe(3) (3) in the presence of p-TolGeH(3) (4) gave a mixture of cia and trans mono(germylene)-bridged diiron co mplexes, CpFe-2(2)(CO)(2)(mu-CO)(mu-Gep-TolH) (cis-5, trans-5), a mix ture of two kinds of trans bis(germylene)-bridged diiron complexes, Cp Fe-2(2)(CO)(2)(mu-Gep-TolH)(2) (syn-trans-6, anti-trans-6), and a com plex with two Fe ... H ... Gs 3-center 2-electron bonds, CpFe-2(2)(CO )(2)(mu-Gep-TolH(2))(2) (7). A cis isomer of complex 6 (syn-cis(H)-6)) was formed as the sole product by the thermolysis of complex 7, Photo lysis of 7 or syn-cis(H)-6 resulted in the conversion to a mixture of syn-trans-6 and anti-trans-6, Reversible thermal and photochemical int erconversion between cis and trans isomers of complex 5 was observed. The molar ratio of the cis and trans isomers of complex 5 in C6D6 was 7:93 at thermal equilibrium at 55 degrees C and 84:16 at the photostat ionary state at 6 degrees C.