Sonogashira Coupling Applied in the Synthesis of 1,2,4-Oxadiazole-Based Nonsymmetrical Liquid Crystals

Hugo Gallardo; Rodrigo Cristiano; André A. Vieira; Ricardo A. W. Neves Filho; Rajendra M. Srivastava

doi:10.1055/s-2008-1032156

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Sonogashira Coupling Applied in the Synthesis of 1,2,4-Oxadiazole-Based Nonsymmetrical Liquid Crystals

Hugo Gallardo*^a, Rodrigo Cristiano^a, André A. Vieira^a, Ricardo A.W. Neves Filho^b, Rajendra M. Srivastava*^b
^a Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, SC 88040-900, Brazil
Fax: +55(48)37216850 ; e-Mail: hugo@qmc.ufsc.br ;
^b Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife, PE 50740-540, Brazil

Abstract

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Abstract

A series of highly π-conjugated nonsymmetrical liquid crystals, based on the core 3,5-(disubstituted)-1,2,4-oxadiazole with a shape similar to a hockey stick, were successfully synthesized by convergent Sonogashira coupling reaction between the building blocks of aryl iodides and the corresponding terminal arylacetylenes, using 3-[4-(decyloxy)phenyl]-5-(haloaryl)-1,2,4-oxadiazoles or decyl 4-iodobenzoate (10) and terminal arylacetylenes. This versatile synthetic route yielded luminescent mesogens with smectic and nematic phases, typical of calamitic compounds.

Key words

Sonogashira coupling - liquid crystals - 1,2,4-oxadiazoles - acetylenes

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References

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