Diastereoisomeric β-ethyl aspartate-cobalt(III) complexes: Λ(+)578- and Δ(-)578-bis(ethane-1,2-diamine)[β-ethyl (S)-aspartato]cobalt(III) bis(perchlorate) monohydrate.
The structures of the diastereoisomers Λ(+)(578)-, (I), and Δ(-)(578)-bis(ethane-1,2-diamine)[β-ethyl (S)-aspartato-κ(2)N,O(1)]cobalt(III) bis(perchlorate) monohydrate, (II), both [Co(C(6)H(10)N(2)O(4))(C(2)H(8)N(2))(2)](ClO(4))(2)·H(2)O, are compared. In both structures, the ester group of the amino acid side chain is engaged only in intramolecular hydrogen bonding to coordinated amine groups. This interaction is stronger in (I) and correlates with previously observed diastereoisomeric equilibrium ratios for related metal complex systems in aqueous media. The two perchlorate anions of (II) are located on twofold axes. Both perchlorates in (I) and one of the perchlorates in (II) are affected by disorder. Both structures exhibit extensive three-dimensional hydrogen-bonding networks.
Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark. anders@kiku.dk
Anders
A
Hammershøi
Magnus
M
Schau-Magnussen
Jesper
J
Bendix
Anne
A
Mølgaard
D000838:Anions / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D026581:Isoaspartic Acid / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010472:Perchlorates / Q000737:chemistry*; D013237:Stereoisomerism
D000838:Anions; D026581:Isoaspartic Acid; D009942:Organometallic Compounds; D010472:Perchlorates; C554370:bis(ethane-1,2-diamine)(beta-ethyl (S)-aspartato)cobalt(III) bis(perchlorate) monohydrate; D003035:Cobalt