Ni-Catalyzed 1,5-Sigmatropic Ester Shift on Cyclopentadiene Rings: Regioselective Conversion of 5,5-Disubstituted Cyclopentadienes to CH2-Cyclopentadienes

Hongyan Bi; Jiaxin Chu; Xiao-Li Zhao; Sunewang R Wang

doi:10.1021/acs.orglett.4c00062

Ni-Catalyzed 1,5-Sigmatropic Ester Shift on Cyclopentadiene Rings: Regioselective Conversion of 5,5-Disubstituted Cyclopentadienes to CH₂-Cyclopentadienes

Org Lett. 2024 Feb 23;26(7):1437-1441. doi: 10.1021/acs.orglett.4c00062. Epub 2024 Feb 12.

Authors

Hongyan Bi¹, Jiaxin Chu¹, Xiao-Li Zhao^{2

3}, Sunewang R Wang^{1

4}

Affiliations

¹ Chang-Kung Chuang Institute, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China.
² Shanghai Key Laboratory of Green Chemistry & Chemical Processes, East China Normal University, Shanghai 200062, China.
³ State Key Laboratory of Petroleum Molecular & Process Engineering, East China Normal University, Shanghai 200062, China.
⁴ Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, Shanghai 200062, China.

PMID: 38345600
DOI: 10.1021/acs.orglett.4c00062

Abstract

Described herein is a nickel(II)-catalyzed regioselective rearrangement of 5,5-disubstituted cyclopentadienes to fully functionalized CH₂-cyclopentadienes via successive 1,5-sigmatropic shifts of the ester group on the quaternary carbon and hydrogen under mild basic conditions. The obtained CH₂-cyclopentadienes were also readily applied in the preparation of highly functionalized dibenzo[e,g]azulene derivatives in two steps.