G. C. Baumann, J. Potenza, S. S. Isied
Feb 1, 1989
Citations
0
Influential Citations
3
Citations
Journal
Inorganica Chimica Acta
Abstract
Abstract The synthesis, X-ray structure and electronic spectra of the title complex are presented,trans Bis(ethylenediamine)chloro(Boc-L-valine)Co(III)-fluoroborate (Boc=t-butyloxycarbonyl) was prepared from trans [Co(en)2OHCl]+ and an active ester form of Boc-L-valine. Blue crystals of CoCl (O4N5C14H34)·BF4 are orthorhombic, space group P212121 with a=13.170(2), b=14.545(2), c=12.6268(8)A, Z=4 and RF(RwF)=0.040 (0.042) for 2087 reflections. The structure consists of [Co(en)2(Boc-L-valine)Cl]+ cations and BF4- anions linked by an extensive hydrogen bonding network involving the BF4 F atoms and the N atoms of the cation. Co(III) is coordinated in a distorted octahedral fashion by four en N atoms, a Cl atom, and a carboxylate O atom from the Boc-L-valine ligand. The coordinated Cl and O atoms are trans and Boc-L-valine acts as a monodentate ligand. The CoN bond lengths (1.943(4)–1.955(4) A) are typical as are the axial CoCl (2.248(1) A) and CoO(CO2)(1.910(3)A) distances. The visible absorption spectrum shows two bands (λ=447, 578 nm) characteristic of trans Co(III)-(en)2L2 complexes.