Synlett 2024; 35(07): 811-815
DOI: 10.1055/a-2179-6438
letter

Ruthenium(II)-Catalyzed Selective C–H Bond Activation of Biindoles and Coupling with Sulfoxonium: An Efficient Access to Pyrido[1,2-a:4,3-b′]diindole frameworks

Ramanna Jatoth
a   Department of Chemistry, Osmania University, Hyderabad-500 007, India
,
Kishan Gugulothu
a   Department of Chemistry, Osmania University, Hyderabad-500 007, India
,
Rasika Meloth Valappil
b   Department of Chemistry, School of Physical Sciences, Central University of Kerala, Kasaragod, Kerala 671320, India
,
Nithya Nelson
b   Department of Chemistry, School of Physical Sciences, Central University of Kerala, Kasaragod, Kerala 671320, India
,
K. Shiva Kumar
a   Department of Chemistry, Osmania University, Hyderabad-500 007, India
b   Department of Chemistry, School of Physical Sciences, Central University of Kerala, Kasaragod, Kerala 671320, India
› Author Affiliations
K.S.K. thanks the University Grants Commission (UGC), New Delhi, for a faculty position under FRP. We also thank CSIR 02(0481)/23/EMR-II for funding this project.


Abstract

A ruthenium-catalyzed selective C–H functionalization/annulation cascade reaction of biindoles and sulfoxonium ylides has been developed. The reaction selectively provides pyrido[1,2-a:4,3-b′]diindole (5H-benzo[2,3]indolizino[7,8-b]indole) derivatives in good yields. A possible mechanism for the reaction pathway is proposed. More importantly, the present study provides a useful method for the construction of pyrido[1,2-a:4,3-b′]diindole frameworks.

Supporting Information



Publication History

Received: 25 May 2023

Accepted after revision: 21 September 2023

Accepted Manuscript online:
21 September 2023

Article published online:
30 October 2023

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