Synlett 2023; 34(01): 29-39
DOI: 10.1055/a-1967-1175
account

Chiral Proton-Transfer Shuttle Catalysts Promoted Enantio­selective Nazarov Cyclization

Jin Cao
a   Frontiers Science Center for New Organic Matters, State Key Laboratory and Institute of Elemento-Organic Chemistry,College of Chemistry, Nankai University, Tianjin 300071, P. R. of China
,
Shou-Fei Zhu
a   Frontiers Science Center for New Organic Matters, State Key Laboratory and Institute of Elemento-Organic Chemistry,College of Chemistry, Nankai University, Tianjin 300071, P. R. of China
b   Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, P. R. of China
› Author Affiliations
We thank National Natural Science Foundation of China (21971119, 92156006), National Key R&D Program of China (2021YFA1500200), the 111 project (B06005) of the Ministry of Education of China, Haihe Laboratory of Sustainable Chemical Transformations, Key-Area Research and Development Program of Guangdong Province (2020B010188001) and the Fundamental Research Funds for the Central Universities for financial support.


Abstract

The Nazarov cyclization reaction is a convenient, widely used method for the synthesis of cyclopentenones. In this account, we reviewed our recent efforts on the chiral proton-transfer shuttle catalysts promoted enantioselective Nazarov cyclization. We have synthesized various chiral cyclopenta[b]indoles and chiral α,α′-disubstituted cyclopentenones by means of cooperative catalysis of a Lewis acid and a chiral spiro phosphoric acid. The mechanistic studies revealed that the chiral spiro phosphoric acid acts as a multifunctional catalyst: it co-catalyzes the cyclization of the dienone and enantioselectively catalyzes a proton-transfer reaction of the enol intermediate via a hydrogen-­bonding network.

1 Introduction

2 Enantioselective Nazarov Cyclization of Indole Enones

3 Enantioselective Silicon-Directed Nazarov Cyclization

4 Conclusion



Publication History

Received: 03 October 2022

Accepted after revision: 24 October 2022

Accepted Manuscript online:
24 October 2022

Article published online:
23 November 2022

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