Crown substituted

The unsymmetrical complexes LnPcPc can also be prepared in a stepwise manner (Scheme 8.1, D, upper part) [87, 112-114]. Treatment of phthalonitrile with excess of Lu(OAc)3- H2Oand DBU gives the half-sandwich compound LuPc(0Ac)(H20)2. The latter complex reacts with Na2Nc in 1-chloronaphthalene leading to the formation of LuPcNc [87]. Similarly, the template reaction of unsubstituted and crown-substituted phthalonitriles with lutetium acetate was carried out in boding w-hexanol in the presence of DBU [115-117]. Bi- and tri-nuclear [118] lutetium complexes could also be obtained following this approach [111, 119]. 

As for the simple crowns, substitution of nitrogen donors for ether oxygens results in systems which exhibit weaker binding towards the... 

Scheme 16. Preparation of crown substituted porphyrazines. [Adapted from (25-27).]...

Aza complexes, with mono-Cp Ti(IV), 4, 417 Aza-crown-substituted ruthenocenes, preparation, 6, 635-636 Aza-Diels-Alder reactions, via silver catalysts, 9, 567... 

With the Fenton system, treatment of excess crown ethers (9) and 2-methylquinoli-nium salt in the presence of FeS04 and r-butyl hydrogen peroxide generates crown-substituted 2-methylquinolines (10) in good yields. Here, the crown ether is selectively... 

Aza-crown substituted cobaltocenium receptors (96) were also prepared and the electrostatic effect of the presence of alkali metal guests in the crown ether rings on the anion-binding process was investigated (215). Evidence for a cooperative anion-binding effect on the addition of sodium ions (due to electrostatic attraction) was presented. The ability of methylated pyridine substituents to electrostatically enhance the anion-binding process has also been reported (216). 

Supramolecular metallocomplex systems on the basis of crown-substituted tetra-pyrroles 04UK6. 

Silica gel Monobenzo crown Substitution reaction of Waddell, Leyden... 

Interesting bis(aza-crown)-substituted chiral crown compounds have been prepared (Lukyanenko et al., 1986). The precursor bis(aza-crown)-substituted chiral diol was prepared by two pathways (method D-5). In the first pathway. 

Epichlorohydrin, when treated with an excess of monoaza-crown, formed the bis(aza-crown) (method D-6) (Belohradsky et al., 1987b). The same bis macrocycle was prepared in a two-step process via an epoxymethyl-substituted aza-crown as shown. Crown-substituted aza-crowns containing an ether linkage were also prepared from the glycidyloxymethyl-substituted crown ethers (see method D-6). 

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