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Updated: Sep 28, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Aza-Büchner-Curtius-Schlotterbeck Reaction Enables Selective Construction of Quaternary Carbon Centers
Simon O Angerer1, Vincent George1, Aryaman Pattanik1
1Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Regensburg, Germany.
Abstract:
Herein, we report the Aza-Büchner-Curtius-Schlotterbeck reaction (ABCS)- a novel method for the uncatalyzed C─C insertion reaction of photogenerated donor-donor diazo compounds into aryl aldimines. The transformation proceeds under very mild conditions and high chemoselectivity, favoring C─C over C─H insertion pathways. In a single step, two C(sp2)─C(sp3) bonds are formed, granting access to homologated imines bearing a newly constructed quaternary carbon center in good yields. Subsequent hydrolysis gave homologated aldehydes, enabling versatile downstream transformations. The diazo intermediate is generated using a continuous-flow microreactor, enhancing both safety and scalability. Mechanistic insights, supported by density functional theory (DFT) calculations, reveal the origins of the observed selectivity and reactivity.
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