Synthesis and photoinduced isomerization of ansa-{eta 5,eta 5 '-[1,1 '-(1-silacyclopent-3-1-diyl)bis(indenyl)]}-dichlorozirconium. The crystal structure of its meso form

ansa-{eta(5),eta(5')-[1,1'-(1-Silacyclopent-3-ene-1,1-diyl)bis(indenyl)]}di chlorozirconium(1a,b) was synthesized. The crystal structure of meso- [(1,4 -CH2CH=CHCH2)Si(C9H6)(2)ZrCl2] (1b) was established by X-ray diffraction an alysis. Photoinduced interconversion of the racemic (la) and mesa forms was studied under various conditions. The photostationary state (rac: meso = 5 5:45) was established rapidly when solutions of ansa-zirconocene were irrad iated with visible light.