Synthesis and Structural Characterization of Azatitanacyclobutane Derivatives
R. Beckhaus , M. Wagner, R. Wang
Eur. J. Inorg. Chem. 1998, 253-256
The titanocene vinylidene intermediate [Cp*2Ti=C=CH2] (9) reacted with the carbodiimides R-N=C=N-R [R = p-CH3C6H4 (19a), C6H11 (19b)] to give the N=C-cycloaddition products [Cp*2Ti-NR-C(=NR)C=CH2] [(R = p-CH3C6H4 (20a), C6H11 (20b)]. The X-ray structure of 20a in form of a surprisingly stable n-hexane clathrate is presented. The azatitanacyclobutane [Cp*2Ti-NPh-C(Ph)(H)-C=CH2] (22) was formed from the reaction between 9 and benzylidene aniline [PhN=C(Ph)H] (21). Reactivity studies showed that azatitanacyclobutanes are unreactive upon typical ring-enlargement reactions as observed for other four-membered titanacycles.