Copper complexes arene

Sigel and co-workers" investigated the interaction between the aromatic rings of phenyl carboxylates (Ph-(CFl2)n-C02) and 1,10-phenanthroline in ternary copper(II) complexes. Variation of the number of methylene units between the aromatic ring and the carboxylate group (n=0-5) revealed that the arene - arene interaction is most pronounced for n=l. This interaction is more efficient in a 60% 1,4-... 

Furthermore, the first direct amination of benzene has been achieved and has generated the aniline derivative in an acceptable yield (Equation (103)). Recently, a cationic copper(i) complex 132-catalyzed nitrene transformation to the C-H bonds of the electron-rich arene was reported by Sadighi and co-workers (Equation (104)).285... 

Rondelez Y et al (2002) The first water-soluble copper(II) calix[6]arene complex presenting a hydrophobic ligand binding pocket a remarkable model for active sites in metalloenzymes. Angew Chem Int Ed Engl 41 1044-1046... 

The calix[6]arene 128 with a syn-arrangement of the a-picolyl groups is < 3v symmetric by its constitution. It forms a copper(I) complex [Cul28X] where the tetrahedral coordination sphere of the copper ion is built up by the three picolyl... 

Arene complexes with mint metals are rather rare. The arene metal bond is weaker compared to the other transition metals and hapticity is lower. For this reason the stronger rr-donor properties of the cyclophanes compared to open chained arenes [109c] make the preparation in benzene solution possible. The cyclophane is simply heated with silver-I (Fig. 29a) [109a] or copper-I (Fig. 29b) [109b] and yields the respective complex formed in almost quantitative yield. It is noteworthy that the silver ion in 128 shows no interaction with the benzene ring at all the naphthalene unit acts as 7t-donor only [109a]. 

R. Cacciapaglia, A. Casnati, L. Mandolini, D. N. Reinhoudt, R. Salvio, A. Sartori, R. Ungaro, Catalysis of diribonucleoside monophosphate cleavage by water soluble copper(II) complexes of calix[4]arene based nitrogen ligands, J. Am. Chem. Soc., 2006, 128, 12322-12330. 

X-ray analysis of both copper(I) (e.g. 9) and copper(II) complexes, independent synthesis, and ammonolysis to the free ligands 35 and 36, confirmed the hydroxylation pathway.42 02-binding and hydroxylation in complex 10 were shown to be sensitive to electronic effects of the para-substituent (X = OMe, Me, C02Me, N02>. Tyrosinase, which contains a dinuclear copper active site strongly resembling the hemocyanine active site, binds O2 reversibly and activates O2 for arene hydroxylation (stoichiometry Cu O2 = 2 These are key features observed in the dinuclear copper complexes shown in... 

It has been shown that the use of ionic liquids may be beneficial in aromatic fluorinations in protic solvents." Aryl fluorides may also be obtained using a copper-catalysed halide exchange reaction. The evidence suggests a redox Cu(I)/Cu(III) catalytic cycle involving oxidative addition of aryl halide at the copper(I) centre followed by halide exchange and reductive elimination." A mechanistic investigation of the palladium-catalysed conversion of aryl triflates to fluorides has shown that C-F reductive elimination from the palladium—arene complex does not occur when the aryl group is electron rich and requires in situ modification of the catalyst." ... 

T -Arene complexes containing late metals have been known for many years, but the scope and utility of these complexes have increased in recent years. Copper(I) and silver form labile arene complexes of various stoichiometries that are apparently T -arene complexes. A few of these complexes have been structurally characterized. More recently, a large number of V-arene and heteroarene complexes of osmium, rhenium, molybdenum, and tungsten have been prepared for the purpose of dearomatization of the arene or heteroarenes. Two examples are shown in Figure 2.33. This dearomatization creates a diene or vinyl unit that imdergoes the organic chemistry of ttiese isolated units, instead of the chemistry of an arene. n -Arene complexes of rhodium and platinum have been characterized structurally and studied in the context of their likely intermediacy in the oxidative addition of arene C-H bonds. ... 

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