U. Steiner, H. Hansen, K. Bachmann
Mar 9, 1977
Citations
0
Influential Citations
32
Citations
Journal
Helvetica Chimica Acta
Abstract
Exo- and endo-Tricarbonyliron Complexes of Bicyclic 2,3-Dimethylidene Compounds. The preparation of exo- and endo-tricarbonyliron complexes (exo- and endo-5, -6, -8, and 9) of 2,3-dimethylidene-5-bicyclo[2.2.1]heptene(1), -bicyclo[2.2.1]-heptane (2), -5-bicyclo[2.2.2]octene (3) and -bicyclo[2.2.2]octane (4) is described. The complexes are obtained by thermal reaction of the bicyclic butadienes with di-ironenneacarbonyl in hexane solution. exo- and endo-5 are also formed photochemically from ironpentacarbonyl and 1 in pentane solution at −35°. The structural assignment of exo- and endo-5 and -6 is based on their mass-spectra and on coordination shifts in 1H- and 13C-NMR.-spectra exo- and endo-6 are correlated with exo- and endo-5, respectively, by hydrogenation. Hydrogenation of the uncomplexed double bond in exo- and endo-5 occurs in both complexes from the exo side as shown by deuteration experiments. The free ligand 1 reacts in the same stereospecific manner.