Reaction of formaldehyde with cyano(ethylenediamine)(glycylglycinato)cobalt(III): crystal structures of cyano(ethylenediamine) [N-(4-carbonyl-4-hydroxymethyl-oxazolidine)glycinato]cobalt(III)·3.5H2O and dicyanobis(ethylenediamine) {μ-N-[N-(((methylimino)methyl)carbonyl)-α-methylserinato)glycylglycinato}dicobalt(III) tetrahydrate

Autor: Ljiljana Solujic, John H. Nelson, Jean Fischer
Rok vydání: 1999
Předmět:
Zdroj: Inorganica Chimica Acta. 292:96-103
ISSN: 0020-1693
DOI: 10.1016/s0020-1693(99)00178-4
Popis: The reaction of [Co(NH2CH2CONCH2CO2)CN(en)] with formaldehyde under basic conditions leads to the formation of four products: cyano(ethylenediamine) [N-(4-carbonyl-4-hydroxymethyl-oxazolidine)glycinato]cobalt(III) ([Co( CH 2 OCH 2 NHC (CH2OH)CONCH2CO2)CN(en)]) (1), dicyanobis(ethylenediamine) {μ-N-(((methylimino)methyl)carbonyl)(α-methylserinato)-glycylglycinato}dicobalt(III) tetrahydrate ([Co(en)CN(CH3NCHCON C(CH 2 OH)CO 2 )-Co(N HCH2CONH2CO2)CN(en)]·4H2O) (2), cyano(ethylenediamine) (N-methylidene-glycylglycinato)cobalt(III) monohydrate ([Co(CH2NCH2CONCH2CO2)CN(en)]·H2O) (3), and cyano(ethylenediamine) (N-hydroxymethylglycylglycinato)cobalt(III) ([Co(HOCH2NHCH2CONCH2CO2)CN(en)]) (4). The products obtained were separated by adsorption chromatography on a cationic exchanger, in the hydrogen form, and characterized by elemental analysis, 1H and 13C NMR spectroscopy. The structures of complexes 1 and 2 were determined by X-ray crystallography. The central features of the investigated reaction are: (a) condensation of formaldehyde takes place with the amino and both of the methylene groups of the coordinated glycylglycine; (b) formation of a binuclear complex in which one of the introduced formaldehyde moieties links two coordinated dipeptidato ligands. A possible mechanism for the reaction is proposed.
Databáze: OpenAIRE
Externí odkaz: