fac-[Re(CO)3(dmso-O)3](CF3SO3): a new versatile and efficient Re(i) precursor for the preparation of mono and polynuclear compounds containing fac-[Re(CO)3]+ fragments

Abstract

We show here that the new complex fac-[Re(CO)3(dmso-O)3](CF3SO3) (1), efficiently prepared in one step from [ReBr(CO)5] and featuring a broad range of solubility, is, in general, a better precursor for the one-step synthesis of mono- and polynuclear inorganic compounds containing fac-[Re(CO)3]+ fragments compared to the commonly used (NEt4)2fac-[ReBr3(CO)3] and fac-[Re(CO)3(CH3CN)3](Y) (Y = PF6, BF4, ClO4) species. Compound 1 is the first example of a Re(I)-dmso complex structurally characterized and confirms the rule that dmso is always O-bonded when trans to CO. The reactivity of 1 was tested in the one-step preparation of several new and known complexes. The O-bonded sulfoxides of 1 are replaced under mild conditions by tri- (L3) and bidentate ligands (L2) to produce fac-[Re(CO)3(L3)]+ and fac-[Re(CO)3(L2)(dmso-O)]+ compounds, respectively. An excess of monodentate ligands (L) and more forcing conditions are needed to prepare fac-[Re(CO)3(L)3]+ compounds. The new compounds include fac-[Re(CO)3(bipy)(dmso-O)](CF3SO3) (4), that turned out to be an excellent precursor for binding the luminescent fac-[Re(CO)3(bipy)]+ fragment to polytopic ligands for the construction of more elaborate assemblies. One example reported here is the two-step preparation of fac-[{Re(CO)3(bipy)}(mu-4,4'-bipy){Ru(TPP)(CO)}](CF3SO3) (8) (TPP = tetraphenylporphyrin). The X-ray structures of the new compounds 1, 4, of the bis-porphyrin complex fac-[Re(CO)3Cl(4'MPyP)2] (13) (4'MPyP = 5-(4'pyridyl)-10,15,20-triphenylporphyrin), and of the rhenium-cyclophane [{(CO)3Re(mu-OH)2Re(CO)3}2(micro-4,4'-bipy)2] (15), among others, are described. Compound 1 might find useful applications in supramolecular chemistry (metal-mediated assembly of large architectures), in the in situ preparation of stable Re compounds to be used in nuclear medicine, and for the labeling of biomolecules.

Aurophilicity versus Mercurophilicity: Impact of d10–d10 Metallophilic Interactions on the Structure of Metal‐Rich Supramolecular Assemblies

“…1 H, 13 C, and 31 P NMR spectra were recorded at RT by using a Bruker AV400 spectrometer. Chemical shifts are reported in parts per million (ppm) relative to Me 4 Si as the external standard.…”

“…[12] The first question raised by this approach is whether it is possible to prepare metal-rich rectangles with organic linkers according to the route used (Scheme 1). Note that, of the few available U-shaped bimetallic molecular clips with short metal-metal distances, [13] to date none have been treated with linkers based on d 10 metal ions that are likely to display metallophilic interactions within the resulting supramolecular assemblies. Other puzzling questions were to know whether the Hg II metal atoms will be forced to be involved in mercurophilic interactions within the resulting assemblies and to see whether intermolecular metallophilic interactions could drive the formation of novel supramolecular organizations.…”

Iminoether Complexes of the Type, fac‐[Re(CO)3L{HNC(CH3)OCH3}]BF4 (L = Bipyridine or a Substituted Bipyridine): Synthesis and Properties

“…[10][11][12][13][14] Our recent work [6,7] indicates that the fac-[Re(CO) 3 -(CH 3 CN) 3 ] + complexes are useful synthons for the preparation of novel compounds where acetonitrile is used as the solvent. [6] However, acetonitrile is a coordinating solvent that inhibits the replacement of the coordinated acetonitrile by the added ligand.…”

Drug Delivery by Water-Soluble Organometallic Cages

“…The fac-Re(CO) 3 corner unit was possibly the first 12+ (a) (the BF 4 anion being represented by spacefilling model) [15], and [Ru 2 {bis(2-pyridylmethylene)benzene-1,4-diamine} 3 ] 4+ (b) [16] Drug Delivery by Water-Soluble Organometallic Cagesorganometallic building block used for the rational design of metalla-cycles and three-dimensional metalla-assemblies [19]. The facial arrangement of the carbonyl groups controls the accessibility of the three remaining coordination sites of the octahedral rhenium centre, thus preventing the formation of polymeric species.…”