Synthesis 2025; 57(01): 176-188
DOI: 10.1055/a-2356-8347
paper
Special Topic Dedicated to Prof. H. Ila

Harnessing the Reactivity of ortho-Alkynylaldehydes: Silver Triflate Catalyzed Regioselective Synthesis of Phosphonylated Fluorescent Molecules

Deepika Thakur
a   Department of Chemistry, University of Delhi, Delhi-110007, India
,
Shivam A. Meena
a   Department of Chemistry, University of Delhi, Delhi-110007, India
,
Sushmita Sushmita
b   Department of Chemistry, Netaji Subhas University of Technology, Dwarka, Delhi-110078, India
,
Akhilesh K. Verma
a   Department of Chemistry, University of Delhi, Delhi-110007, India
c   Institution of Eminence (IoE), University of Delhi, Delhi-110007, India
› Author Affiliations
The research work was funded by Science and Engineering Research Board (CRG/2022/008887) and IoE/2021/12/FRP.


Dedicated in Honor of Prof. H. Ila

Abstract

An efficient approach for the facile synthesis of phosphonylated 1,3-dihydrofuro[3,4-b]quinolines and dihydrofuro[3,4-b]pyridines is developed. Reaction proceeds by the formation of new C–P and C–O bonds affording Z-selective phosphonylated products at room temperature. Diphenylphosphine oxides and dialkyl phosphites are explicitly incorporated into the carbonyl carbon of o-alkynylaldehydes in good to excellent yields. The reaction exhibits mild conditions, broad substrate scope, and the formation of three new bonds in the presence of a silver catalyst. The mechanistic studies revealed that the reaction proceeded via an ionic pathway in a 5-exo-dig manner to give Z-selective products, which was validated by X-ray crystallographic studies. Photophysical studies of selected compounds revealed the emission maxima in the range of 455 nm.

Supporting Information



Publication History

Received: 22 May 2024

Accepted after revision: 27 June 2024

Accepted Manuscript online:
28 June 2024

Article published online:
22 July 2024

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