A. Pinkerton, G. Chapuis, P. Vogel
1979
Citations
0
Influential Citations
36
Citations
Journal
Inorganica Chimica Acta
Abstract
Abstract The reaction of 2,3,5,6-tetrakis(methylene)bicyclo[2.2.2]octane (1a) with Fe 2 (CO) 9 yields the two (η 4 -1,3-diene)Fe(CO) 3 isomers (2: exo; 3:endo) together with two bimetallic isomers (C 12 H 14 )[Fe(CO) 3 ] 2 (4:endo-exo; 5:diexo). The reaction of 1a with Ru 3 (CO) 12 yields the endo-(C 12 H 14 )Ru(CO) 3 (6) and endo, exo-(C 12 H 14 [Ru(CO) 3 ] 2 (7) complexes as the main products. The molecular structure of 3 has been determined by X-ray crystallography. The Fe(CO) 3 group is in the endo position with respect to the roof-shaped tetraene. The ligand is bound through one diene group to two basal positions of a tetragonal pyramidal Fe(CO) 3 L 2 moiety. Hydrogen atom positions have been determined (final residual R = 0.029). The dimensions for the 1,3-butadieneirontricarbonyl system, as found in this and 41 other structures, are summarized and discussed statistically. In this study the weighted averages for all structures show the threeCC distances to be of equal length and the FeC (inner) distance to be shorter than the FeC (outer) distance. The deviations of H(Z) and H(E) atoms from the butadiene plane, as found in this and 6 other structures having an exocyclic unsubstituted 1,3-diene group, are also discussed. Neither thermal epimerization of iron nor epimerization catalyzed by H + were found for complexes 2 – 7 whose structures in solution were deduced from their 1 H and 13 C NMR data on the basis of the known structure of 3.