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Updated: Aug 5, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Deacylative SN2'-Type Alkylation of Monochloro- and gem-Dichlorocyclobutenones Mediated by Pro-aromatic Intermediates
Pinku Prasad Mondal1, Sourav Das1, Keerthana Somaraj1
1School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551Kerala, India.
Abstract:
We report a mild, redox-neutral deacylative SN2'-type alkylation of monochloro- and gem-dichlorocyclobutenones with pro-aromatic ketone-derived dihydroquinazolinones enabled by visible light photocatalysis. The method uniquely combines the C-C bond cleavage of unstrained aliphatic ketones with concurrent C-C bond formation via α-selective radical addition to the enone moiety of gem-dichlorocyclobutenones, contrasting β-selective radical addition in Giese-type addition. This base- and oxidant-free method provides efficient access to highly functionalized 4-alkylated α-chlorocyclobutenones. Furthermore, aldehyde-derived pro-aromatic 4-alkyl-1,4-dihydropyrides served as C-radical precursors, enabling the synthesis of 4-alkylated α-chlorocyclobutenones under similar reaction conditions.
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