Cy clams

Ni(III) complexes oxidize some substrates. For example, [Ni(cy-clam)]3+ oxidizes hydroquinone and catechol in aqueous perchlorate media. The kinetics of the reactions have been studied (122). 

Disregarding this aspect, and since cyclam is an interesting core for constructing den-drimers because it can be easily functionalized and because despite its absence of spectroscopic properties, it can interact in such a way with dendrons as to modify their photophysical properties, the interaction of lanthanide ions with cy clam-based dendrimers has been investigated. The dendrimers are constmcted from the cyclam core fitted with four dimethoxyben-zene and eight naphthyl units (generation 1, fig. 81) second generation introduces a total of 12 dimethoxybenzene and 16 naphthyl moieties. Coordination to Lnm ions occurs in acetoni-trile/methylene chloride (Ln = Nd, Eu, Gd, Tb, and Dy), but no sensitized Ln-luminescence was observed (Saudan et al., 2004). Another example of a macrocycle-based dendrimer is discussed below in section 3.3.2. 

An intramolecular electronic energy transfer leading to Cr" emission takes place in the multi-component system 2 [6]. After the irradiation on the [Ru"(bpy)2(CN)2] luminescent fragment, the excitation is transferred to one of the -[CNCr (cy-clam)CN] subunits, whose emission spectrum is observed. However, it should be noted that system 2 does not really belong to the class of two-component sensore as... 

Rotating-copper-disk electrode techniques have been used to evaluate the efficiency of the nickel macrocycle catalyst for the reduction of CO2 to Studies have been performed using Ni(diazacyclam) + (diazacyclam = 3,10-dimethyl-1,3,5,8,10,12-hexaazacyclophane) (5.6), a complex derived from cy-clam, which appears to be more active than [Ni(cyclam)2] " under the same conditions (see Figure 5.70) . These results are consistent with a mechanism proposed by other authors - . ... 

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