Durene cores

With the dendrimers series shown in Fig. 1, the order of AE° values was H2PO4- > HS04 > Cl" > NO3-. This order can, however, vary greatly from one dendrimer series to the other, and the same can be said of the dendritic effect some dendrimer families (such as the above one) give a strong dendritic effect for a given anion, and others do not. For instance, an amido-ferrocenyl dendrimer with an octabenzylated durene core and 24 redox termini underwent values of the order of what was found for the dendrimer 9-Fc of Fig. 1, far less than 18-Fc of Fig. 1. 

The publication in which compound 5 was reported concerned variation of organic cores as a route that disrupts the AgSOs layered structure and potentially forms open framework materials. In addition to the mesitylene core already mentioned, silver(I) networks were reported with a,a, a",a" -durenetetrasulfonate (LIO), to form [Ag4(L10)(H2O)2] ao, 13, and 1,3,5,7-tetra(4,4 -sulfonophenyl) adamantane (Lll), to form [Ag4(Lll)(H20)2] 1.3H20 oo, 14. Compound 13, based on the durene core, formed a three-dimensional structure (Fig. 12) but not that of a pillared layered type. 

In the same way as the hexafunctionalization of hexamethylbenzene leads to stars, the octafunctionalization of durene leads to dendritic cores (Scheme 12). 

If the hexafunctionalization of hexamethylbenzene leads to stars, the octafunctionalization of durene leads to dendritic cores. The first of these octaalkylation reactions was reported as early as 1982, and led to a primitive dendritic core containing a metal-sandwich unit. Thus, as the hexafunctionalization, this reaction is very specific. Two hydrogen atoms in each methyl group are now replaced by two methyl, allyl, or benzyl groups (Scheme 11.4).19 Applications to the synthesis of dendrimers containing 8 or 24 redox-active groups have recently been reported.20... 

Regioselective chlorocarbonylation with oxalyl chloride and AICI3 in dichloro-methane at 15 °C of polybenzyl cores 1269 resulting from the CpFe+-induced oc-tabenzylation of durene has been reported [953]. Reaction of the resulting polychlorinated cores with amines and alcohol nucleophiles has opened new rapid synthetic routes toward dendritic materials. 

If deprotonation of a polymethylbenzene complex is carried out in the presence of an excess base and compatible electrophile such as an alkyl iodide or allyl- or benzyl bromide, the deprotonation-alkylation sequences spontaneously follow one another in situ until steric inhibition is reached. This reaction has been exploited with arene = CgMeg for the synthesis of star-shaped molecules (examples below) and living polymers and with arene = durene or mesitylene for the synthesis of dendritic cores (see for instance Chap. 21.2.2). 

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