Metal Complexes of Biologically Important Ligands, CLXXIV [1]. Palladium(II) and Platinum(II) Complexes with Schiff Bases from 2-(Diphenylphosphino)benzaldehyde and α-Amino Acid Esters

A series of palladium(II) and platinum(II) complexes Cl2M(P-N-O) (M = Pd, Pt) with bidentate Schiff bases (P-N-O) from 2-(diphenylphosphino)benzaldehyde and α-amino acid esters has been synthesized, using PdCl2 or K[PtCl3(C2H4)], respectively. Abstraction of chloride from Cl2M(P-N-O) (using AgBF4) has afforded the cationic complexes [(P-N-O)M(Cl)]+BF4− in which the Schiff bases function as tridentate ligands with coordination of the ester group. The structures of Cl2Pd(Ph2PC6H4C(H)=N-CH2CO2Et) and of [(Cl)Pd(Ph2PC6H4C(H)=NC(H)(CH2CH=CH2)CO2Me)]+BF4− have been determined by X-ray diffraction. Complexes (L)MCl2 and [(L)MCl]+BF4 (M = Pd, Pt) have also been prepared with the reduced Schiff base Ph2PC6H4CH2NHC(H)(CH2Ph)CO2Me.

Download Full-text

Metal Complexes of Biologically Important Ligands, CLXXV [1]. Pentamethylcyclopentadienyl Halfsandwich Complexes of Rhodium(III) and Iridium(III) with Schiff Bases from 2-(Diphenylphosphino)- benzaldehyde and α-Amino Acid Esters

Zeitschrift für Naturforschung B ◽

10.1515/znb-2010-0603 ◽

2010 ◽

Vol 65 (6) ◽

pp. 679-686 ◽

Cited By ~ 5

Author(s):

Bernhard Schreiner ◽

Barbara Wagner-Schuh ◽

Wolfgang Beck

Keyword(s):

Schiff Base ◽

Amino Acid ◽

Schiff Bases ◽

Ester Group ◽

Tridentate Ligand ◽

Molar Ratio ◽

Amino Acid Esters ◽

X Ray Diffraction ◽

X Ray ◽

Acid Esters

The reactions of the chlorido-bridged complexes [Cp*M(Cl)(μ-Cl)]2 (M = Rh, Ir) with Schiff bases (P-N-O) from 2-(diphenylphosphino)benzaldehyde and α-amino acid esters afford the complexes Cp*M(Cl)2(P-N-O) in which the ligands function as monodentate P donors (M = Ir) or as bidentate P-N donors (M = Rh). These complexes can be converted into cationic complexes [Cp*M(Cl)(P-NO)]+ with bidentate P-N ligands by treatment with NH4PF6. The cationic complexes [Cp*M(Cl)(PN- O)]+Cl− have been detected also in solutions of Cp*M(Cl)2(P-N-O). The P-N-coordinated complex [Cp*Rh(Cl)(Ph2P-C6H4-C(H)=N-C(H)(CH2Ph)CO2Me)]+PF6− was characterized by X-ray diffraction. From Cp*M(Cl)2(P-N-O) and AgBF4 or AgPF6 (molar ratio 1 : 2) the dicationic complexes [Cp*M(P-N-O)]2+ are formed in which the ester group is also coordinated to the metal atom. The Schiff base from 2-(diphenylphosphino)benzaldehyde and allylglycine ester acts as a tridentate ligand, however with coordination of the C=C allyl group instead of the ester function.

Download Full-text

Metallkomplexe mit biologisch wichtigen Liganden, CXV. Addition von α-Aminosäureestern an [CpFe(CO)3]+: Carbamoylkomplexe Cp(OC)2Fe-C(O)NHCHRCO2R’ und Kristallstruktur von Cp(OC)2Fe-C(O)NHCH2CO2Et / Metal Complexes of Biologically Important Ligands, CXV. Addition of α-Amino Acid Esters to [CpFe(CO)3]+: Carbamoyl Complexes Cp(OC)2Fe-C(O)NHCHRCO2R' and Crystal Structure of Cp(OC)2Fe-C(O)NHCH2CO2Et

Zeitschrift für Naturforschung B ◽

10.1515/znb-1999-0316 ◽

1999 ◽

Vol 54 (3) ◽

pp. 385-388 ◽

Cited By ~ 14

Author(s):

Reinhold Urban ◽

Kurt Polbom ◽

Wolfgang Beck

Keyword(s):

Crystal Structure ◽

Amino Acid ◽

Metal Complexes ◽

Amino Acid Esters ◽

X Ray Diffraction ◽

Carbonyl Ligand ◽

X Ray ◽

Acid Esters

α-Amino acid esters can be added to a carbonyl ligand of [CpFe(CO)3]+CF3SO3- to give the carbamoyl complexes Cp(OC)2Fe-C(O)NHCHRCO2R′ (R = H, Me, CHMe2, CH2Ph; R′ = Et, Me). This type of reaction may be useful for the marking of peptides at the amino end. The crystal structure of Cp(OC)2Fe-C(O)NHCH2CO2Et was determined by X-ray diffraction.

Download Full-text

Metal complexes of biologically important ligands, LXXVIII. Synthesis of palladium complexes of ferrocenyl-substituted amino acid derivatives

Canadian Journal of Chemistry ◽

10.1139/v95-143 ◽

1995 ◽

Vol 73 (7) ◽

pp. 1164-1174 ◽

Cited By ~ 33

Author(s):

Doris Freiesleben ◽

Kurt Polborn ◽

Christian Robl ◽

Karlheinz Sünkel ◽

Wolfgang Beck

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Metal Complexes ◽

Palladium Complexes ◽

Amino Acid Derivatives ◽

Amino Acid Esters ◽

X Ray Diffraction ◽

Chelate Complexes ◽

X Ray ◽

Acid Esters

Schiff bases from ferrocene aldehyde and α-amino acidates react with PdCl2 or Na2PdCl4 to give N,O-chelate complexes (2a–e, 3). The related N-ferrocenylmethylen-α-amino acid esters give, with Pd(OAc)2, cyclopalladated acetate-bridged complexes (4a,b). N,O-chelate complexes (5–7) are obtained from Na2PdCl4 with N-ferrocenylmethyl prolinate and-alaninate as well as with N,N-dibenzyl glycinate. The ethyl ester of N,N-dibenzylglycine and Pd(OAc)2 form the cyclopalladated acetate-bridged complex 8, while the ester of N-monobenzylglycine and Na2PdCl4 affords trans-PdCl2(L)2 with a monodentate N-coordinated ligand. The structures of 2a, 4a, 5, 7, and 9 were determined by X-ray diffraction. Keywords: ferrocene, amino acids, palladium(II) complexes, crystal structures.

Download Full-text

Metallkomplexe von biologisch wichtigen Liganden, CVI [1]. Metallkomplexe von Donor-substituierten Oxazolin-5-onen sowie von Bis(oxazolin-5-onen) / Metal Complexes of Biologically Important Ligands CVI [1], Metal Complexes of Donor Substituted Oxazolones and of Bis(oxazolones)

Zeitschrift für Naturforschung B ◽

10.1515/znb-1998-0906 ◽

1998 ◽

Vol 53 (9) ◽

pp. 965-972 ◽

Cited By ~ 5

Author(s):

Markus Prem ◽

Werner Bauer ◽

Kurt Polbom ◽

Wolfgang Beck

Keyword(s):

Amino Acid ◽

Metal Complexes ◽

Nucleophilic Addition ◽

Metal Salts ◽

Amino Acid Esters ◽

X Ray Diffraction ◽

Chelate Complexes ◽

X Ray ◽

Close Proximity ◽

Acid Esters

A series of chelate complexes 1-12 of Cu(II), Ni(II), Pd(II), and Ru(III) with the anion of 2-(2′-hydroxyphenyl)-5(4H)-oxazolone and with 2-(2′-aminophenyl)-5(4H)-oxazolone were prepared from metal salts or from chloro-bridged complexes [(R3P)MCl2]2 (M = Pd, Pt) and [(p-cymene)RuCl2]2. Nucleophilic addition of α-amino acid esters to the bis-chelate complexes M(oxophenyloxazolone)2(M = Ni, Cu) gave the dipeptide derivatives 13-18. Dinuclear Pd(II) and Pt(II) chelate complexes 19-23 were obtained from phenylene- and ethylenebridged bis(oxazolones). The structures of (Et3P)(Cl)Pd(O,N-oxophenyloxazolone) (6) and of Cl2(Et3P)Pt(2,2′-phenylene-bis(4-methyloxazolone)Pt(PEt3)Cl2 (20) were determined by X-ray diffraction. In complex 20 a close proximity of two phenylene H atoms to the metal is observed.

Download Full-text