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Adv Synth Catal
; 362(19): 4092-4097, 2020 Oct 06.
Article
in English
| MEDLINE
| ID: mdl-33162875
ABSTRACT
We report an enantioselective Nazarov cyclization catalyzed by chiral hydrogen-bond-donors in concert with silyl Lewis acids. The developed transformation provides access to tri-substituted cyclopentenones in high levels of enantioselectivity (up to 95% e.e.) from a variety of simple unactivated dienones. Kinetic and mechanistic studies are consistent with a reversible 4π-electrocyclization C-C bond-forming step followed by rate- and enantio-determining proton-transfer as the mode of catalysis.