Rhenium carbonyl derivatives

Paralleling an earlier study,new molecular squares have been constructed using octahedral rhenium carbonyl derivatives as the corner units. The resulting products are photoluminescent - a potentially useful property for use in sensing applications that involve inclusion of an appropriate guest molecule into the cavity of the... 

Examples of the promotion of orthometallation by oxygen donors are limited to side chains containing ketonic and amide carbonyl groups. The use of ketone oxygen as the donor atom to promote orthometallation has been reported only for manganese and rhenium carbonyl derivatives ... 

Reaction of the manganese and rhenium carbonyls, M2(CO)10, with Ru3(CO)12 or Os3(CO)12 in a 3 1 ratio yields the products [M(CO)5]2M (CO)4, with M = Re or Mn, M = Ru or Os. These are considered to be linear trinuclear metal systems. The only other trinuclear carbonyl derivative isolated is OsCo2(CO)n, obtained as one of a number of compounds from the reaction of Co2(CO)8 with H2Os(CO)4. No structural data are available for this compound (241). 

The existence of the neutral rhenium carbonyl [Re(C0)4] was first claimed in 1965 206 but, although it is easily sublimed, it has not yet been characterized by mass spectrometry and the value of n is still not known. This colourless substance [v (CO) 2055 and 1995 cm-1 in CHC13] has been obtained as a by-product in the synthesis of Re2(CO)i0 starting from Re2S7, copper powder, and carbon monoxide at 85 atm, 200 °C206>. There has also been a report of the compound Re4(CO)10(PPh2Me)6, which can be considered to be a substitution product of the hypothetical species, Re4(CO)i6 it has been obtained by a photochemical reaction between Re2(CO)j0 and PPh2Me194. In both cases, and particularly in the phosphine derivative, a tetrahedral structure seems improbable because of steric constraints. 

Table 13. Enthalpy of formation, AHf (g) and disruption, AH (kj mol x) of alkyl and acyl derivatives of manganese and rhenium carbonyls...

To model the photochemical reaction of Re2(CO)io with silica in the presence of THE, silanolates other than silsesquioxanes [Et3SiOH, PhsSiOH, Ph2Si(OH)2 and (OH)Ph2SiOSiPh2(OH)j with [Re2(CO)8(THE)2] have also been synthesized [148], pointing to the formation of the surface species [((r-=SiO)((r-H)Re2(CO)8j in the above-mentioned reaction with silica. Rhenium carbonyl of the two diol derivatives listed above where both the SiOH have reacted are proposed as models for surface reaction with a vicinal hydroxyl residue, although no direct surface species is reported [148]. 

Top S, El Hafa H, Vessieres A, Quivy J, Vaissermann J, Huges DW, McGlinchey MJ, Momon JP, Thoreau E, Jaouen G (1995) Rhenium carbonyl complexes of 0-estradiol derivatives with high affinity for the estradiol receptor an approach to selective organometallic radiopharmaceuticals. J Am Chem Soc 117 8372-8380... 

Top, S., El Hafa, H., Vessieres, A., Quivy, J., Vaisseraiann, J., Hughes, D. W., McGlinchey, M. J., Momon, J.-P., Thoreau, E., Jaouen, G. (1995). Rhenium carbonyl complexes of 3-estradiol derivatives with high affinity for the estradiol receptor An approach to selective organometallic radiopharmaceuticals, J. Am. Chem. Soc., 117 8372. 

Manganese and rhenium carbonyls form organosulfur and organoselenium derivatives of the types [REM(CO)4] (R = methyl, ethyl, n-butyl, phenyl, p-tolyl, etc. ... 

Schiff bases provide useful mixed donor sets. The carbonyl function of the most frequently used ligands is derived from either 1,3-dicarbonyl compounds or salicylaldehyde. Favourable combinations involve O-, N- and S-donor atoms. A range of technetium and rhenium complexes exist with bi-, tri-, tetra- and pentadentate ligands. The geometry of these complexes depends on the number and type of coordinating atoms as well as on the chain length between the donor atoms in the SchifF-base ligands. 

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