Vanadocene complexes of amino acids containing secondary amino group: The first evidence of O,O-bonded carboxylic group to vanadocene(IV) moiety

Reaction of vanadocene dichlorides (Cp2VCl2 and (η5-C5H4Me)2VCl2) with amino acids containing secondary amino groups gives three types of complexes: a) compounds with N,O-bonded amino acid, b) O-bonded amino acids and c) O,O-bonded amino acid. The complexes with N,O-bonded amino acid and O-bonded amino acids were observed in the case of l-proline and N-methylglycine (NMG). Reactions with N-phenylglycine (NPG) give O,O-chelates as the sole products. All three types of the complexes were characterized by spectroscopic methods. Structures of [(η5-C5H4Me)2V(O-Pro)][BPh4], [Cp2V(O-Pro)2][PF6]2, [Cp2V(N,O-NMG)][BPh4]·MeOH, [(η5-C5H4Me)2V(N,O-NMG)][BPh4]·MeOH, [Cp2V(O-NMG)2][Cl]2·2H2O, [(η5-C5H4Me)2V(O-NMG)2][Cl]2·H2O and [(η5-C5H4Me)2V(O,O-NPG)][BPh4] were determined by X-ray crystallography.

Graphical abstractReaction of vanadocene dichloride with amino acids containing secondary amino groups gives three types of complexes.Figure optionsDownload full-size imageDownload as PowerPoint slide