Metallkomplexe mit biologisch wichtigen Liganden, XXXIV. Allyl‐Palladium(II)‐ und Triphenylphosphan‐Gold(I)‐Komplexe mit Nucleobasen und Nucleosiden

Abstract

The reactions of (~3-allyl)Pd(~-C1)2Pd(q3-allyl) (A) and (COD)Rh(p-C1)2Rh(COD) with nucleobases and nucleosides give the complexes (q3-C,H5)Pd(L)CI (1) (L = inosine, adenosine, guanosine, cytosine, cytidine, 2-thiouraci1, 2-thiocytosine) and (COD)Rh(cytosine)Cl (2), respectively. With adenosine and purine also ligand bridged complexes (q3-C,H5)(CI)Pd -L-Pd(Cl)(q3-C3H5) (3) have been obtained. Ph3PAuCI reacts with the anions L' of purine, adenine, uridine, and inosine to give the complexes Ph3PAuL' (5). Ph3PAui is added to both N atoms of the dianion of uracil with formation of 6. The coordination of the nucleobases is discussed on the basis of the 'H and 13C NMR spectra. The X-ray structure of Ph3PAu(adeninate) (5 b) has been determined.In Fortsetzung unserer Arbeiten uber das komplexchemische Verhalten von Nucleobasen') berichten wir im folgenden uber Reaktionen des dimeren, chloroverbrdckten q3-Allyl-Palladiumkomplexes (q3-C3H5)Pd(p-C1,)Pd(q3-C3Hj) (A) sowie von (Triphenylphosphan)gold(I)-chlorid, Ph,PAuCI, mit neutralen und anionischen Nucleobasen und Nucleosiden. Komplex A reagiert rnit zahlreichen N-Donoren L unter Spaltung der Chlorobrtkcken zu monomeren Verbindungen des Typs (C3H,)Pd(CI)L3). Mit Gold-(111)-chlorid wurden verschiedene Nucleobasen-Komplexe beschrieben4). Es ist bekannt, daR sich Chlorid in Ph,PAuCI durch verschiedene anionische N-Heterocyclen, z. B. Azol-Anionen, substituieren laBt5). Agruwul et al. erhielten antitumoraktive Goldkomplexe aus Ph,PAu(acetat) und verschiedenen Pyrimidinbasen sowie 6-Mercaptopurin6).

Time-Dependent Molecular Rearrangement of [Au(N9-adeninate)(PTA)] in Aqueous Solution and Aggregation-Induced Emission in a Hydrogel Matrix

“…This coordination mode of cationic (phosphine)gold(I) units to N 9 has been repeatedly observed for different phosphine ligands, including PTA, and causes it to be energetically favored by approximately 38 kJ mol −1 with respect to other donor positions such as N 7 . 22 The observed bond distances fit well with those reported for similar (adeninate)gold (I) examples ([Au(N 9 -adeninate)(PMe 3 )], 21 Au−P 2.233(3), 2.231(3) Å, Au−N 2.048(10), 2.043(10) Å; [Au(N 9 -adeninate)(PEt 3 )], 30 Au−P 2.238(2) Å, Au−N 2.057(5) Å; [Au(N 9 -adeninate)(PPh 3 )], 31 Au−P 2.240(1) Å, Au−N 2.038(4) Å; [{Au(N 9 -adeninate)} 2 (μ-dppp)], 32 Au−P 2.2347 (11) S2). Absorption Properties.…”

“…Unluckily, those gold (I) products are unstable toward decomposition under the acidic atmosphere, precluding the collection of complete data. The identity of the precipitate was unequivocally revealed by treating an equimolecular mixture of [Au(N 9 -adeninate)-(PTA)] and [Au(N 9 -adeninate)(PMe 3 )], stirred in distilled water for 24 h, with aqueous HCl and by studying the formed precipitate by 31 P{ 1 H} NMR spectroscopy (see Figure S17).…”

(1,3-Dimethyl-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-7-yl)(dimethylphenylphosphine)gold(I)

“…The steric hindrance from the N3--CH3 group may explain why N7 is favoured over N9. Where ligands lack the N3--CH3 group, Au also coordinates to N9 as in, for example, adeninato(triphenylphosphine)gold(I) (Rosopulos, Nagel & Beck, 1985). In view of this, the coordination in the present complex would be expected to take place through N7.…”

Bis(4-hydroxymethyl-1,5-dimethylimidazole-N3)gold(I) chloride

“…Comment Gold(I) is relatively soft and is stabilized by softligand atoms such as S and P or light atoms involved in rr bonding to other atoms, as in cyanide, isonitriles and carbenes. Ligands bound through O or N atoms are much less effective at stabilizing Au I (Cotton & Wilkinson, 1988), unless the N atom is part of an aromatic ring system (Rosopulos, Nagel & Beck, 1985;Lock & Turner, 1987). We have investigated the reaction of aromatic amine-substituted phosphines with Au ~ compounds and, generally, obtained complexes in which the Au atom is bound to the P atom (Howard- Lock, Lock, Penny & Turner, 1989).…”