Cyrhetrenylimines and cyrhetrenylamines: Synthesis, characterization and X-ray crystal structure

Cyrhetrenyl Schiff base derivatives of the form (eta(5)-C5H4CH=NAr)Re(CO)(3), [Ar=Ph (1a) C6H4OMe-p (l b) and C6H4NO2-p (1c)] have been prepared from cyrhetrenylcarbaldehyde and the corresponding aromatic amines. H-1 and C-13 NMR indicates that these compounds have the anti-(E) conformation in solution and the X-ray crystal structure of 1b confirms that it also adopts the anti-(E) form in the solid state. Further reaction of cyrhetrenylaldimines 1 with sodium borohydride in methanol produces quantitatively, the corresponding amine derivatives (eta(5)-C5H4CH2-NHAr)Re(CO)(3) [Ar=Ph (2a) C6H4OMe-p (2b) and C6H4NO2-p (2c)]. All these cyrhetrenylamines were characterized by IR,H-1 and C-13 NMR, MS. Additionally, 2b has been characterized structurally. (C) 2008 Elsevier Ltd. All rights reserved.