DIASTEREOSELECTIVE SYNTHESIS OF NITROGEN-CONTAINING HETEROBICYCLIC AND HETEROTRICYCLIC SKELETONS VIA INTRAMOLECULAR CYCLIZATION OF (ETA(4)-DIENE)FE(CO)(3) COMPLEXES BEARING AMINO-ACID DERIVATIVES

Addition of secondary amino acid derivatives to (eta(5)-pentadienyl)tr icarbonyliron cations gives (eta(4)-diene)tricarbonyliron complexes in high yields with amino ester groups at the terminal position of the d iene ligands. Treatments of the adducts containing a sarcosine, phenyl alanine, or alanine moiety with lithium diisopropylamide (LDA), under an atmosphere of carbon monoxide, furnish fused 3-azabicyclo[3.3.0]oct anecarboxylic acid derivatives. Under the same reaction conditions, in tramolecular cyclizations of complexes containing a proline or pipecol inic acid derivative at the terminal position of the diene ligands giv e 8-azatricyclo[6.3.0.0(2,6)]undecane and 7-azatricyclo[7.3.0.0(2,7)]d odecane ring systems, respectively, whereas treatment of the complex c ontaining a nipecotic acid derivative provides a bridged 8-azatricyclo [6.3.1.0(2,6)]dodecanecarboxylic acid derivative.