Ferrocenylethenylsilatranes and a cymantrenylsilatrane

Abstract The syntheses, properties and crystal structures of two isomeric ferrocenylethenylsilatranes and 1-(3-methylcymantrenyl)silatrane are reported. The organometallic moieties and the silatrane show little structural influence on each other. The SiN distances remain in the expected range of 2.13–2.22 A, asserting the hypervalency of silicon. The electron-donating effect of the silatrane group is transmitted through the CC double bond to ferrocene, as shown by the redox potentials. The first hyperpolarizability of the ferrocene derivatives was determined by hyper-Rayleigh scattering.