Reactions of Cp2TiR (R = Cl, C6F5, C6H5, o-CH3C6H4) with R′NC (R′ = o-CH3C6H4, 2,6-(CH3)2C6H3) give two types of products: terminally coordinated adducts, Cp2TiR · CNR′, and insertion products, Cp2TiC(R)NR′, i.e. iminoacyl derivatives. Insertion of the isocyanide group into the TiR bond was followed by IR spectroscopy for Cp2Ti-o-CH3C6H4 · 2,6-(CH32C6H3NC. The iminoacyl compounds are readily oxidized by X2 (X = I, SC6H5) to give Cp2Ti(X)C(R)NR′. The CN group in the latter compound is η2-coordinated to titanium. © 1979.