Aromatization-driven deconstructive functionalization of spiro dihydroquinazolinones via dual photoredox/nickel
Hong-Jie Miao1, Jin-Hua Zhang1, Wenke Li1
1School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China guoln81@xjtu.edu.cn.
Abstract:
Aromatization-driven deconstruction and functionalization of spiro dihydroquinazolinones via dual photoredox/nickel catalysis is developed. The aromatization effect was introduced to synergistically drive unstrained cyclic C-C bond cleavage, with the aim of overcoming the ring-size limitation of nitrogen-centered radical induced deconstruction of carbocycles. Herein, we demonstrate the synergistic photoredox/nickel catalyzed deconstructive cross-coupling of spiro dihydroquinazolinones with organic halides. Remarkably, structurally diverse organic halides including aryl, alkenyl, alkynyl, and alkyl bromides were compatible for the coupling. In addition, this protocol is also characterized by its mild and redox-neutral conditions, excellent functional group compatibility, high atom economy, and easy scalability. A telescoped procedure involving condensation and ring-opening/coupling was found to be accessible. This work provides a complementary strategy to the existing radical-mediated C-C bond cleavage of unstrained carbocycles.
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