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.

Automated summary

It was found that replacing trimethylsilylacetylene with triisopropylsilylacetylene can improve the yield of 5-alkynyl bicycloporphyrins. The synthesized 5-alkynyl benzoporphyrins exhibit semiconductor characteristics, and other derivatives were synthesized through coupling and retro Diels-Alder reactions.