Chaipot Kanganavaree,[a] Kritchasorn Kantarod,[a] Thanapat Worakul,[a] Darunee Soorukram,[a],[b] Chutima Kuhakarn,[a],[b] Khetpakorn Chakarawet,[a] Worawat Wattanathana,[c] Panida Surawatanawong,[a],[b] Vichai Reutrakul,[a],[b] and Pawaret Leowanawat*[a],[b]
[a] Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Rd, Bangkok 10400, Thailand, E-mail: pawaret.leo@mahidol.ac.th
[b] Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand
[c] Department of Materials Engineering, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand

We successfully developed an efficient synthesis of 1,2-disubstitutedacenaphthylene derivatives via a palladium-catalyzed double decarboxylative annulation of naphthalicanhydrides with 1,2-disubstituted acetylenes. This method features broad substrate scope and good functional group compatibility, enabling the synthesis of diverse 1,2-disubsti-tuted acenaphthylenes, including 1,2-diaryl-, 1,2-dialkyl-, and1-aryl-2-alkyl substituted acenaphthylenes. The reaction likely proceeded through a double decarboxylation and alkyne insertion sequence and could be applied for the synthesis of various 1,2-diarylacenaphthylene derivatives, including 1,2-diarylacenaphthylene dicarboximides (3r and 3s) and non-alternant 1,2-diarylacenaphthylene (3u). Single-crystal X-ray diffraction analysis unambiguously confirmed the structures of 3r and 3u with two twisted phenyl substituents connected to planar and nonplanar conjugated skeleton, respectively. The optical properties of 1,2-diarylacenaphthylene derivatives were investigated. Whereas 1,2-diphenylacenaphthylene dicarboximide 3r exhibited an enhanced charge transfer CT process from the diphenyl donor, the π-extended dicarboximide 3s showed only a locally excited (LE) state transition. Further applications of this method for the synthesis of other cyclopentannulated polycyclic aromatic hydrocarbons (CP-PAHs) and their properties are currently in progress.

Acknowledgement: This project is funded by National Research Council of Thailand (NRCT) and Mahidol University (N42A650367), Faculty of Science, Mahidol University (Fundamental Fund: fiscal year 2023 by the National Science Research and Innovation Fund (NSRF)). The authors thank the Center of Excellence for Innovation in Chemistry (PERCH-CIC) for scientific instrumental support. The Science Achievement Scholarship of Thailand (SAST) is gratefully acknowledged for the financial support to K.K.

Reference: Kanganavaree, C.; Kantarod, K.; Worakul, T.; Soorukram, D.; Kuhakarn, C.; Chakarawet, K.; Wattanathana, W.; Surawatanawong, P.; Reutrakul, V.; and Leowanawat, P. J. Org. Chem. 2024, 89, 20, 15083–15090

DOI: https://doi.org/10.1021/acs.joc.4c01747