SUBSTITUENT EFFECTS ON THE CHEMICAL REACTIVITIES OF TRICARBONYL AND TETRACARBONYL IRON COMPLEXES OF 7-AZANORBORNADIENE DERIVATIVES

The intermediates of nitrene-extrusion reaction were found in the form s of (ANB)Fe(CO)4 or (ANB)Fe(CO)3 during the reaction of 7-azanorborna diene derivatives (ANB) with diiron nonacarbonyl. By using extended Hu ckel molecular orbital (EHMO) calculation, we found that the chemical behavior of these complexes is correlated with the nature of substitue nts of ANB. The relative reactivity of (ANB)Fe(CO)4 and (ANB)Fe(CO)3 i s influenced by the charge distributions on iron and nitrogen. In the crystal structure of (ANB)Fe(CO)4 an angular distortion of Fe-C=O is o bserved, which is a result of donor-acceptor interaction between the l one-pair of N and the pi orbital of CO.