The modulation of selectivity of highly reactive carbon radical cross-coupling for the construction of C-C bonds represents a challenging task in organic chemistry. N-Heterocyclic carbenes (NHCs) catalyzed radical transformations opened...

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Allyl radicals served as a crucial intermediate in the radical functionalization of fundamental raw materials and received increasing attention. Despite the significance, allyl-radicals-participated radical cross-couplings were rare and mainly focused...

1,3,5-tri-substituted benzene rings emerged with unique properties has widespread applications in materials, boosting the rapid development of their synthesis. Despite the significance, the direct construction of hetero-1,3,5trisubstituted benzene core was far less-developed. Herein, we realized a DBU-mediated isomerization/6-π electro-cycliza-tion/oxidative aromatization cascade of sulfonyl-substituted allenyl ketones under an air atmosphere (DBU = 1,8diazabicyclo[5.4.0]undec-7-ene). This versatile protocol featured metal-free conditions, easy operation, and broad functional group tolerance provides a new avenue for the construction of hetero-1,3,5-tri-substituted benzene.

The modulation of selectivity of highly reactive carbon radical cross-coupling for the construction of C-C bonds represents a challenging task in organic chemistry. N-Heterocyclic carbenes (NHCs) catalyzed radical transformations opened a new avenue for acyl radical cross-coupling chemistry. With this method, highly selective cross-coupling of acyl radical with alkyl radical for efficient construction of C-C bonds were succussfully realized. However, the cross-coupling reaction of acyl radical with vinyl radicals represents an uncharted domain. We herein describe NHCs and photocatalysis co-catalyzed radical 1,4-sulfonylacylation of 1,3-enynes, providing structurally diversified valuable tetrasubstituted allenyl ketones. Mechanistic studies indicated that ketyl radicals are formed from aroyl fluorides via oxidative quenching process of excited photocatalysis, allenyl radicals are generated from chemo specific sulfonyl radical addition to the 1,3-enynes, finally, unprecedented key allenyl and ketyl radical cross-coupling provides tetrasubstituted allenyl ketones.