Synthesis Of 5-Alkynyl Bicycloporphyrins As A Synthon Of 5-Ethynyl Bicycloporphyrin

5-Alkynyl bicycloporphyrins (5-alkynyl CPs) were obtained by Sonogashira coupling reaction of trimethylsilylacetylene and 5-bromo CP in low yield. Triisopropylsilylacetylene has low volatility and is bulky, and its use in place of trimethylsilylacetylene markedly improved the yields of 5-alkynyl CPs. The semiconductor characteristics of the synthesized 5-alkynyl benzoporphyrins (5-alkynyl BPs) were evaluated. We also synthesized BP dimer and 5-phenylethynyl BPs containing an ethynylbenzene derivative by coupling reaction and retro Diels-Alder reaction. (C) 2021 Elsevier Ltd. All rights reserved.