Thus, gold(iii) favours a mechanism in which the ketone is preferentially activated leading to cyclisation with concomitant 1,2-halogen migration through bromonium intermediate 5, whereas gold(i) coordinates to the allene leading to cyclisation without halogen migration via 6.
In the GkPOT study the first crystal structure was obtained with a sulfate ion coordinated in the same position as the phosphono moiety of the peptide, i.e. coordinated to Glu310 (Fig. 3) [51].
It consists of a gold(I) center linearly coordinated to triethylphosphine and to 3,4,5 triacetyloxy-6- acetyloxymethyl)oxane-2-thiolate, triacetyloxy-6- acetyloxymethyl
CN− is an imperfect mimic of compound I (with two atoms coordinated to the iron versus one oxygen), so potentially the larger halides could bind productively at site Br1 after compound I is formed.
Here we present the preparation of 14 pairs of cis- and trans-diammine monochlorido platinum II) complexes, coordinated to heterocycles (i.e., imidazole, 2-methylimidazole and pyrazole) and linked to various acylhydrazones, which were designed as potential inhibitors of the selenium-dependent enzymes glutathione peroxidase 1 (GPx-1) and thioredoxin reductase 1 (TrxR-1).
For 5, only one oxygen of L2 coordinated to Ag(I) ions.
In complex 1, L1 ligands are coordinated to Ag(I) metal centers in rare tridentate fashions, forming one-dimensional (1-D) ladder-like structure, which is interlinked by L2 anions to generate 2-D pleated molecular sheet.
Single-crystal X-ray diffraction revealed that four terminal and three bridging oxygen atoms of the Wells Dawson cluster are coordinated to Cu(I) ions and form an unprecedented hepta-supporting polyoxometalate.
DFT calculations suggest that this transformation takes place through silicenium cations 272 formed by a pericyclic reaction of the allylsilylalkynes coordinated to gold(I).
Experimental data and DFT calculations supported that the second step of the reaction is initiated by protonation of the double bond of the sulfenylated allylic alcohol with a proton donor coordinated to gold(I) chloride.
