Neutral donor ligands

Complexes of the type [AuRL] may contain a great variety of organic ligands such as alkyl, aryl, vinyl, or alkynyl, whereas the neutral donor ligand L is most commonly a tertiary phosphine. Also many polynuclear complexes are known which have the C-Au-L moiety with bridging polyfunctional ligands. Alkyl- or aryl-gold(I) complexes are usually synthesized... 

Adjusting the accessibility of the lone pair of electrons on the neutral donor ligand by variation of R... 

The literature contains numerous reports of complexes formed between mercury(II) halides, HgX2 (X = Cl, Br, I), and neutral donor ligands containing the donor atoms N, P, As, Sb, S, Se or Te. Some of these species are described in subsequent sections. For a recent survey consult ref. 555 and papers cited therein. 

The dimers have turned out to be a very interesting and useful class of metalloporphyrins which was extended to dimers containing two divalent metal ions with Rh-Rh single (see Sect. 3.3), Re-Re triple, and Mo-Mo or W-W quadruple bonds [49,222-224]. These species react with many donor and acceptor molecules (see the following Sects. 3.22 and 3.3). The reactions with typical neutral donor ligands may be seen in Scheme 1, the oxidation reactions in Scheme 2. 

In the presence of neutral donor ligands L (e.g. L = Py, 1-Meim, THT), and an excess of a reductant, e.g. dithionite or hydrazine, dioxo complexes are transformed into bisligandmetal(II) species (ruthenochromes or osmochromes paths j,k). The logic intermediate in such a four-electron reduction, an oxometal(IV) porphyrin, was only observed for M = Ru (path j, P = OEP, TMP R = EtOH) when norbornene served as a mild oxygen acceptor. 

Reactions of Metal Halocarbonyls with Neutral Donor Ligands... 

Reactions of [Wl2(CO)(NCMe)(r)2-RC2R)2] (R = Me, Ph) with Neutral Donor Ligands... 

A wide variety of organochromium species with neutral donor ligands are accessible, mainly of the trivalent and divalent metals. Notable among these are the Cr(III) type, LjCrR X3 n, most of which are prepared by the action of RMgX on CrCl3 3 THF. 

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