No abstract

A short literature review on the reactions of various chlorobridged complexes with α-aminoacidates, α-amino acid esters, peptide ester or derivatives of amino acids is given. The chloro bridged o-palladated N,N-dimethylferrocenecarbothioamide [(fct)Pd(µ-Cl) 2 Pd(fct)] reacts with the anions of glycine, L-alanine, L-proline, L-valine, L-phenylalanine, L-leucine, L-isoleucine to give the N,O-chelates [(fct)Pd(N,O-α-aminocarboxylate)] Einleitung Chloroverbrückte Komplexe [2] L n M(µ-Cl) 2 ML n sind ideale Ausgangsverbindungen für die Synthese von metallorganischen Komplexen mit Aminosäuren und deren Derivaten [3]. Sie setzen sich mit den Anionen von Aminosäuren unter Spaltung der Chlorobrücken und Substitution von Chlorid zu N,O-Chelaten L n M(NH 2 CHRCO 2 ) um. Mit Neutralliganden wie a-Aminosäure-bzw. Peptid-Estern oder Schiff-Basen von Aminosäuren reagieren chloroverbrückte Komplexe meist nur unter Öffnung der Chlorobrücken. Im Folgenden sind die halogenoverbrückten Komplexe aufgeführt, die mit Aminosäure-Anionen und Aminosäure-Derivaten umgesetzt wurden: [(ON) 2 M(µ-Cl)] 2 (M ϭ Fe,Co) [4], [(allyl)Pd(µ-Cl)] 2305 (1Ϫ7). Due to the planary chirality of the unsymmetrically disubstituted cyclopentadienyl iron moiety of fct the complexes 2Ϫ7 with optically active amino acidate ligands are formed as a mixture of two diastereoisomers, which can be detected by their NMR spectra.

Metal Complexes of Biologically Important Ligands. CLXVI Metal Complexes with Ferrocenylmethylcysteinate and 1,1′‐Ferrocenylbis‐(methylcysteinate) as Ligands A series of complexes of transition metal ions ( Cr3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+ ) and of lanthanide ions ( La3+, Nd3+, Gd3+, Dy3+, Lu3+ ) with the anions of ferrocenylmethyl‐L‐cysteine [(C5H5)Fe(C5H4CH(R)SCH2CH(NH3+)CO2−] (L1) and with the dianions of 1,1′‐ferrocenylbis(methyl‐L‐cysteine) [Fe(C5H4CH(R)SCH2CH(NH3+) CO2−)2] (R = H, Me, Ph) (L2) as N,O,S‐donors were prepared. With the monocysteine ferrocene derivative L1 as ligands complexes [MIIL12] or [CrIIIL12]Cl type complexes are formed whereas the bis(cysteine) ligand L2 yields insoluble complexes of type [ML2]n, presumably as coordination polymers. The magnetic moments of [MnIIL2]n, [PrIIIL2]n(OH)n and [DyIIIL2]n(OH)n exhibit “normal” paramagnetism.

The chiral orthometallated palladium complex (S)-[Pd{C6H4 (CH(CH3)N(CH3)2 )-C,N}Cl]2 (1) can be used as a reagent for the determination of the enantiomeric ratio of α-amino acids. By reaction of 1 with mixtures of several D- and L-α-amino carboxylates diastereoisomers of the α-amino acidato complexes 2a - g are obtained. 1NMR determination of the ratio of the diastereoisomers provides the D/L-ratio of the used D- and L-α-amino carboxylates and is therefore a simple method for the determination of the enantiomeric ratio of α-amino acids.

Metal Complexes of Biologically Important Ligands. CLXIII N,O‐Chelate Complexes with PropargylglycinateThe N,O‐chelate complexes with propargylglycinate(L), CuL2, NiL2, [(Ph3P)2Pd(L)](BF4), (o‐Tolyl)(Ph3P)Ni(L), (Di‐otolylphosphino)benzylPd(L) have been prepared and characterized by spectroscopic methods.