Synthesis and Characterization of Oligoproline-Based Molecular Assemblies for Light Harvesting

Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
The Journal of Organic Chemistry (Impact Factor: 4.72). 08/2006; 71(14):5186-90. DOI: 10.1021/jo0603936
Source: PubMed


Helical oligoproline arrays provide a structurally well-defined environment for building photochemical energy conversion assemblies. The use of solid-phase peptide synthesis (SPPS) to prepare four such arrays, consisting of 16, 17, 18, and 19 amino acid residues, is described here. Each array contains the chromophore [Rub'(2)m](PF(6))(2) (b' = 4,4'-diethylamidocarbonyl-2,2'-bipyridine; m = 4-methyl-2,2'-dipyridine-4'-carboxylic acid) and the electron transfer donor PTZ (phenothiazine). The arrays differ systematically in the distance between the redox-active metal complex and PTZ sites. They have been used in photophysical studies to provide insight into the distance dependence of electron transfer. (J. Am. Chem. Soc. 2004, 126, 14506-14514). This work describes the synthesis, purification, and characterization of the oligoproline arrays, including a general procedure for the synthesis of related arrays.

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