Metallkomplexe mit biologisch wichtigen Liganden, LVIII. C ‐Allylglycin‐ und C ‐Vinylglycin‐Komplexe von Palladium(II), Platin(II), Rhodium(III), Iridium(III) und deren Reaktionen mit Nucleophilen

Metal Complexes of Biologically Important Ligands, LVIII. – C ‐Allylglycine and C ‐Vinylglycine Complexes of Palladium(II), Platinum(II), Rhodium(III), Iridium(III) and Reactions with Nucleophiles The synthesis of the complexes (R 1 3 P)(Cl 2 Pt( C ‐allylglycine ester) ( 1 ), ( 2 ) and of (η 5 ‐C 5 Me 5 )Ir( C ‐allylglycinate) ( 6 ) with tridentate O,N ,η 2 ;‐ CC allylglycinate as ligand is described. Addition of enolates (Nu − ) to the coordinated CC bond of 2 gives the γ‐ C ‐metallated α‐amino acid ester complexes ( 3 ). In most cases the platination occurs stereoselectively to yield the five‐membered metallacycle with the substitutents CH 2 Nu and CO 2 R 2 in trans position. From 3d the new α‐amino acid H 2 NCH(CO 2 Me)‐(CH 2 ) 3 C(Ph)(CO 2 Et) 21 ( 4 ) is cleaved. The structures of 3c and 6 have been determined by X‐ray diffraction. C ‐Vinylglycinate can be stabilized at the metal atom in the complexes ( 10 ) (MRh, Ir).