Oligophenylenes functionalization

D.M., Beck, P.A. and Strongin, R.M. (2000) Convenient iterative synthesis of an octameric tetracarboxylate-functionalized oligophenylene rod with divergent end groups. Organic Letters, 2, 3201 1. 

This modular methology involves the repetition of directed protection/cyclo-addition/deprotection steps, and allows for the synthesis of monodisperse dendritic oligophenylenes of the first (46a, 22 benzene rings) and second (46b, 62 benzene rings) generation [60]. Within the synthetic sequence, the authors made use of the different reactivities of protected and deprotected ethynylene functions within the key cycloadditon step. 

M. D (2004) Synthesis and functional properties of strongly luminescent diphenylamino end-capped oligophenylenes. The Journal of Organic Chemistry, 69, 921-7. 

Figure 16.38, Melting points of oligophenyls and oligophe-nylenes as a function of the degree of polymerization I, p-oligophenyls 2, acyclic m-oligophenyls 3, cyclic m-oligophenylenes 4, acyclic o-oligophenyls and 5, cyclic o-oligophcnylenes Adapted from Angew. Cheni. 7(11), 835 (1968), with permission of VCH, Weinheim.

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