Reducing sugars and sodium hydroxide react with phthalonitrile and 4-methoxyphthalonitrile to form mixtures of the phthalocyanine and oligomers. The oligomers, obtained in yields up to 54%, were deduced to have a structure that is predominantly polyazine with the o-cyanophenyl group as a substituent from elemental analysis and spectral data. Since carbohydrate related compounds lacking the reducing linkage gave no products, it is suggested that the observed reactions require the a-hydroxycarbonyl grouping.

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C o n j u g a t e d M a t e r i a l s : P r o s p e c t s f o r S y n t h e s i s U s i n g C a r b o h y d r a t e R e a g e n t s Abstract: General considerations related to the use of sugars and closely related compounds as reagents for molecular and macromolecular synthesis are presented. For the first time, we have used unprotected carbohydrates to initiate polymerizations. A variety of dicyanoalkenes and -arenes react with sugars in the presence of alkali to give conjugated polymers. Both cyclopolymerization and polymerization at only one of two cyano groups are observed, and some qualitative mechanistic issues related to these observations are discussed. In some cases, a sugar alkoxide is the active initiating reagent. Characterization of the resulting polymers is reported. Alkaline sugar reagents have also been used in Knoevenagel reactions to synthesize CN-PPV oligomers and a related conjugated polymer in good yields. The use of the polysaccharide chitosan as a polycation allows the absorption spectrum of the polythiophene HPURET to shift to longer wavelengths than other polycations in electrostatically assembled films.

Phthalonitrile and its derivatives react with Tin(II) reagents to give intensely colored linear oligomers. Structures are proposed for the oligomers based on elemental analysis, infrared, 1H and 13C spectra, and mass spectra. Stannous chloride has two kinds of properties, reducing reagent and Lewis acid. Tin(II) alkoxide initiates phthalonitrile oligomeriaztion when excess alkoxide is present. The mass spectrum indicates a chain length of at least a hexamer. In semi-empirical AM1 calculations, the helical conformation of a pentamer is indicated to be more stable than a linear conformation. The position of the electronic spectral maximum can be controlled by different kinds of reaction conditions and solution absorption and emission spectra were recorded.

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