Sonogashira Coupling Applied in the Synthesis of 1,2,4-Oxadiazole-Based Nonsymmetrical Liquid Crystals
作者:Hugo Gallardo、Rajendra Srivastava、Rodrigo Cristiano、André Vieira、Ricardo Neves Filho
DOI:10.1055/s-2008-1032156
日期:2008.2
A series of highly Ï-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.
Abstract New nonlinear compounds containing 1,4‐diaryl‐[1,2,3]‐triazole were prepared using a straightforward and efficient method for the regioselective synthesis of [1,2,3]‐triazoles. The methodology consists of a Cu(I)‐catalyzed 1,3‐dipolarcycloaddition of arylazides to terminal arylacetylenes (click reaction). All compounds exhibited liquid‐crystalline profile.