Microwave-assisted C–C bond formation of diarylacetylenes and aromatic hydrocarbons on carbon beads under continuous-flow conditions

• Published in: Communications chemistry Vol. 6; no. 1; p. 78
• Main Authors: Yamada, Tsuyoshi, Teranishi, Wataru, Sakurada, Naoya, Ootori, Seiya, Abe, Yuka, Matsuo, Tomohiro, Morii, Yasuharu, Yoshimura, Masatoshi, Yoshimura, Takeo, Ikawa, Takashi, Sajiki, Hironao
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 24.04.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 639/638/224/685; 639/638/549/908; 639/638/549/976; 639/638/77/887; Activated carbon; Aromatic compounds; Aromatic hydrocarbons; Bonding; Catalysts; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Contamination; Continuous flow; Covalent bonds; Dehydrogenation; Hydrocarbons; Microwave absorption; Oxidizing agents; Platinum; Residues; Stoichiometry; Synthesis
• ISSN: 2399-3669; 2399-3669
• DOI: 10.1038/s42004-023-00880-y

The synthesis of polycyclic aromatic compounds generally requires stoichiometric oxidants or homogeneous metal catalysts, however, the risk of contamination of inorganic residues can affect their properties. Here we present a microwave (MW)-assisted platinum on beaded activated carbon (Pt/CB)-catalyzed C–C bond formation of diarylacetylenes and aromatic hydrocarbons under continuous-flow conditions. Various fused aromatic compounds were continuously synthesized via dehydrogenative C(sp 2 )–C(sp 2 ) and C(sp 2 )–C(sp 3 ) bond formation with yields of up to 87% without the use of oxidants and bases. An activated, local reaction site on Pt/CB in the flow reaction channel reaching temperatures of more than three hundred degrees Celsius was generated in the catalyst cartridge by selective microwave absorption in CB with an absorption efficiency of > 90%. Mechanistic experiments of the transformation reaction indicated that a constant hydrogen gas supply was essential for activating Pt. This is an ideal reaction with minimal input energy and no waste production. The synthesis of polycyclic aromatic compounds generally requires stoichiometric oxidants or homogeneous metal catalysts, however, the risk of contamination of inorganic residues can affect their properties. Here, the authors develop a microwave-assisted platinum on beaded activated carbon-catalyzed C–C bond formation of aromatic compounds under continuous-flow conditions.