Heterocycles, ligands

The Ti -coordinated Mn(CO)3 cationic complexes of thiophenes follow mainly from the direct interaction of a heterocyclic ligand with Mn(CO)5X (81HCA1288). The first successful synthesis of 79 (R = = H = Me, R = R" =... 

Classification and analysis of crystallographic and structural data for Sn-com-plexes with heterocyclic ligands 98MI65. 

Stereochemistry of complexes with heterocyclic ligands 95MI1. 

Stereoselective asymmetric synthesis with participation of diazocarbonyl intermediates in the presence of catalysts possessing chiral heterocyclic ligands 97CC983. 

Luminescent polynuclear metal complexes with heterocyclic ligands 99CSR323. 

Mono- and polymetallic lanthanide-containing functional assemblies with heterocyclic ligands 99CSR347. 

Technetium-chelates with heterocyclic ligands 98CSR43. 

Competitive coordination of ambident heterocyclic ligands in metal complexes 97UK434. 

Making and breaking the dioxygen 0—0 bond with participation of synthetic copper complexes with heterocyclic ligands 97ACR227. 

Pd-catalysts with heterocyclic ligands as catalysts for Heck reaction 98CSR427. 

Zn-complexes with heterocyclic ligands as fluorescent probes for biological investigations 98CSR179. 

Bimetallic catalysis by binuclear complexes of Cu, Fe, Mn, Ni, Pd, and Rh with heterocyclic ligands 98T12985. 

Complexes of rf-elements with heterocyclic ligands as promising components of non-silver photographic systems 97UK735. 

Versatile supramolecular helicatedmetal complexes with N-heterocyclic ligands 97CRV2005. 

Isolation and characterization of stereoisomers in di- and trinuclear complexes with N-heterocyclic ligands 98CSR185. 

Metal complexes with heterocyclic ligands in medicine 99AG(E)1512. 

Pt-complexes with heterocyclic ligands and Pt-chelates as antitumor drugs 99CRV2451. 

Synthesis of chelates (including those with heterocyclic ligands) by direct interaction of ligands with metals or metal oxides, particularly using electrochemical or tribochemical activation 97MI41. 

L = C3H3, C H ) and then [Rh(acac)(CO),] to yield the tetranuclear species 180 (85ICA(i00)L5), where the heterocyclic ligands are tridentate. The product reacts with the rhodium(I) dimer [Rh(CO)2Cl]3 to give the trinuclear complex 181. In the solid state, the molecules of this complex form the intermolecular stacks along the z-axis. 

Dimethyl-l,2,2,3-tetramethyl-A -1,2,5-azasilaboroline with [Fe2(CO)9] gives sandwich 62 and sandwich 63 (82AGE207, 82CB738) with Cp)Co(C2H4)2]. With [Ni(CDT)] or in a vapor phase with metallic nickel, sandwich 64 (M =Ni) is formed. The vapor-phase synthesis with iron gives 64 (M = Fe). In all these sandwiches, 62-64, the j " -coordination of the heterocyclic ligand is realized. 

The surprising stability of N-heterocyclic carbenes was of interest to organometallic chemists who started to explore the metal complexes of these new ligands. The first examples of this class had been synthesized as early as 1968 by Wanzlick [9] and Ofele [10], only 4 years after the first Fischer-type carbene complex was synthesized [2,3] and 6 years before the first report of a Schrock-type carbene complex [11]. Once the N-heterocyclic ligands are attached to a metal they show a completely different reaction pattern compared to the electrophilic Fischer- and nucleophilic Schrock-type carbene complexes. 

Treatment of [MeC(NBu02]2CrCl(THF) with the potassium salts derived from pyrazoles and 1,2,4-triazoles as outlined in Scheme 121 afforded the corresponding derivatives with 3,5-disubstituted pyrazolato or 3,5-disubstituted 1,2,4-triazolato ligands in 65-70% yields. X-ray structural analyses revealed / -coordination of the heterocyclic ligands... 

As was suggested in the preceding discussion, most of the arene complexes isolated by metal-atom techniques are benzene derivatives. However, heterocyclic ligands are also known to act as 5- or 6-electron donors in transition-metal 7r-complexes (79), and it has proved possible to isolate heterocyclic complexes via the metal-atom route. Bis(2,6-di-methylpyridine)Cr(O) was prepared by cocondensation of Cr atoms with the ligand at 77 K (79). The red-brown product was isolated in only 2% yield the stoichiometry was confirmed by mass spectrometry, and the structure determined by X-ray crystal-structure analysis, which supported a sandwich formulation. 

Au( N) CI3 adducts are readily obtained by reaction of AU2CI6 or [ AuCU] with a variety of substituted heterocyclic ligands including 2-phenylpyridine [9], 2-benzylpyridines [10],... 

A variety of gold(III) complexes of carboxamido substituted heterocyclic ligands are obtained by reaction of [AuCh] with the appropriate ligands, these include [Au (N,N )Cl2j (HN,N =picolinamide) (IS) [70], [Au(N,N, N")Cl]Cl [N,N H,N" = N-(8-quinolyl)pyridine-2-carboxamide (16), N-(8-quinolyl)glycine-2-carboxamide (17) or N-(8-quinolyl)-L-alanine-2-carboxamide (18)] [71] (Figure 2.11). 

Figure 2.11 Complexes of carboxamido substituted heterocyclic ligands.

Scheme 3.22 Sulfur-containing A/,0-heterocycle ligands for addition of ZnEt2 to...

ZnEt2 to chalcone with mercaptocam-phan-2-ol-derived hgand 96-7 A, 0-heterocycle ligands 120 (+)-5-e/7i-nojirimycin-5-lactam, synthesis of 338, 340 Noyori, Ryoji 2... 

The copper(I) analogue [Cu(L)][C104] (758) (distorted pseudotetrahedral) of complex (294) was prepared and its properties investigated.258 Using a bis(diazine) heterocyclic ligand structure of the complex (759) was determined. 64... 

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