The structure of bicyclic ferrocenylmethylene substituted 2-pyrazolines and their reactions with azodicarboxylic acid N-phenylimide

Asymmetrical induction in the synthesis of bicyclic pyrazolines with a ferr ocenyl substituent has been studied. A relatively high diastereomeric selec tivity in the 'chiral-center-by-a-chiral-center' induction of the 1,2-type has been observed. Molecular geometry of a cis-diastereomer of 1-acetyl-9-f errocenyl-4-ferrocenylmethylene-1,2-diazabicyclo[4.3.0]non-2-ene has been e stablished. Bicyclic 2-pyrazolines having conjugated ferrocenylmethylene fr agments interact with azodicarboxylic acid N-phenylimide to form diene and monoene adducts. (C) 1999 Elsevier Science S.A. All rights reserved.