Rhenium tricarbonyl complexes

Scheme 28. Manganese and rhenium tricarbonyl complexes with sohd phase linkers (68).

Table 1 Rhenium tricarbonyl complexes with multidentate ligands...

Rhenium tricarbonyl complexes containing substituted cyclopentadi-enyl and bis diphenylphosphine ligands also were investigated as anticancer agents. The antiproliferative effects on breast cancer of complex A shown in Fig. 23 were examined relative to the known active metabolite, 4-hydroxy tamoxifen, and found to have a similar effect [107]. The cytotoxicity of five rhenium tricarbonyl bis-diphenylphosphine complexes B shown in Fig. 23 was examined for 18 different human cancer cell lines. The tests showed that all the complexes were active against specific tumor cell lines, especially a line of breast and uterine cancer [108]. 

Understandably, there is an enormous richness in the photophysical and photochemical behavior of the excited states present in diimine rhenium tricarbonyl complexes. Indeed, this plethora of molecular photophysical characteristics has led to a wide range of interesting and important applications, including their use as catalysts [21-25], sensors [26-33], probes for photo-polymerization [10, 34, 35], optical switches [36 15], light-emitting materials [46-52], nonlinear optical materials [53-56], binding or photocleavage of DNA [57-61], and radiopharmaceuticals [62-66], Under the purview of this article our focus will be to cover photophysical and photochemical properties and hence other aspects, such as synthetic, catalytic, pharmaceutical, etc., will not be discussed. 

One drawback of rhenium tricarbonyl complexes, /bc-[Re(bpy) (COlaL]", is that their absorption of visible light is weak (see... 

Mixed-ligand rhenium tricarbonyl complexes anchored on a (k2-H, S) trihydro(mercaptoimidazolyl)borate A missing binding motif for soft scorpionates Mo 1 V/ /Re oc / 84... 

Lo and coworkers also reported an interesting application of a complex of this family, this time as sensor for Zn " and Cd ions [68]. To do so, they prepared 21, a rhenium tricarbonyl complex, and 22 (Scheme 11.5), the same molecule coupled with a tyramine-derived 2,2 -dipicolylamine (DPAT) imit known as a chelator of Zn " and Cd " ions. In vitro studies showed that 21 was luminescent, while 22 was not This is due to the quenching of fluorescence induced by the DPAT ligand. However, limiinescence was recovered after addition in the medium of Zn " " or Cd " ions. FeasibiUty of using 22 as biosensor for these two cations has been demonstrated on HeLa cells incubated in the presence of 22... 

Fig. 6 A rhenium tricarbonyl complex conjugated to a bombesin analogue and an inter-calator, compound 7, visualised in fixed PC-3 cells by fluorescence microscopy (left), where green represents the complex and blue the DAPI nuclear stain.

Rhenium tricarbonyl complexes containing two N-alkyimidazole Hgands and one pyridine were synthesized by the reaction of [Re(CO)3(N-RIm)2(OTf)] (which in turn is easily prepared from the reaction of [Re(CO)5(OTf)] and N-alkyhmidazoles) with either pyridine or... 

Cuesta L, Hevia E, Morales D, et al. Activation of a 1,10-phenanthrohne Hgand on a rhenium tricarbonyl complex. Chem Commun. 2005 116—117. 

Espinal Viguri M, Huertos MA, Perez J, Riera L. Imidazole-nitrile or imidazole-isonitrile C—C coupling on rhenium tricarbonyl complexes. Chem Eur J. 

This new heteroscorpionate is a potential building block for copolymers with methylmethacrylate and ethylene glycol dimethacrylate able to mimic the 2-His-l-carboxylate facial triad and capable to produce copolymer-bound manganese and rhenium tricarbonyl complexes.M(CO)3 derivatives (M = Mn or Re) containing two tris(oxazolinyl)phenylborate Hgands (Scheme 25) demonstrated to produce significant structural protection... 

Villaume S, Daniel C (2005) Emission spectroscopy of metal-to-ligand-charge-transfer states of HRe(CO)3(H-DAB), model system for alpha-diimine rhenium tricarbonyl complexes. Comptes Rendus Chimie 8 1453-1460... 

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