Methane, 2,2 -dipyrryl

As in the [22]porphyrin(3.1.3.1) series, the cyclohexene moieties being part of the bridges originate from the preparation of the dimers from dimethylpyrrole and a hydronaphthalene diketone by acid-catalyzed condensation. The synthetic approach developed by Franck2b has the advantage over the foregoing method that more stable conventional pyrroles and dipyrryl-methanes can be used to form the macrotetracycle in a stepwise manner. 

Dipyrryl-methane (z. B. Bilirubin) und deren Abkommlinge kuppeln mit zwei Mol Diazonium-Salzen unter Spaltung der Methylen-Brucke zu zwei Mol Azo-Verbindung3. Das Brucken-C-Atom lafit sich mit 5,5-Dimethyl-l, 3-dioxo-cyclohexan (Dimedon) als Formal-dehyd nachweisen ... 

Prof. Battersby s laboratory in Cambridge, is that deaminase has a dipyrryl-methane cofactor which consists of two previously formed PBG units. This cofactor acts as an anchor on to which four more PBG units are attached, to form an open chain hydroxybilane intermediate. After cleavage from deaminase, this intermediate acts as the substrate for cosynthestase. 

The next step is shown in Scheme 9.19 prerotaxane 232+(PF6 )2, 3,5-di-r-butylbenzaldehyde 1818 and (diethyl-3,3 -dimethyl-4,4 -dipyrryl-2,2 )methane 2423 (molar ratio 1 4 10) are mixed and stirred in dichloromethane, in the presence of trifluoroacetic acid (3 1) for 17 h. Subsequently, a large excess of p-chloranil (30 1) is added in order to oxidize the intermediate porphyrinogens and the reaction mixture is heated under reflux for 1.5 h. After work-up and chromatographic separation, three porphyrins are isolated the etio-por-phyrin 24, the desired Cu(I) [2]-rotaxane 252+(PF6 )2 and the compartmental bis-copper(I) [3]-rotaxane 264+(PF6")4. Copper(I) [2]-rotaxane 252+(PF6")2 is isolated in 25% yield (Scheme 9.19). 

Fig.5 Synthesis of the various [2]- and [3]rotaxanes (i) CH2CI2/CH3CN, room temperature (ii) di-fert-butyl-3,5-benzaldehyde, (diethyl-3,3 -dimethyl-4,4 -dipyrryl-2,2 )methane 4, CF3COOH, CH2CI2, room temperature, then chloranil, CH2CI2, reflux...

N2B1O2C6H9, Benzene, l,2-dihydioxy-4,5-diamino-, hydrobromide, 33 115 N2C5Hg, Pyrazole, 3,5-dimethyl-, complexes with tungsten, 33 219 N2C9H10, Methane, 2,2 -dipyrryl-, 33 59 N2Cl6Fe2OCi6H40, Ferrate(3-), /i-oxo-hexa-chlorodi-, bis(tetraethylammonium),... 

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