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. 2024 Mar 26:12:1371978.
doi: 10.3389/fchem.2024.1371978. eCollection 2024.

Photoinduced radical tandem annulation of 1,7-diynes: an approach for divergent assembly of functionalized quinolin-2(1H)-ones

Daixiang Chen  1 , Zhi-Jie Song  1 , Shenghu Yan  1 , Guigen Li  2 , Jia-Yin Wang  1 , Yue Zhang  1
Affiliations

Photoinduced radical tandem annulation of 1,7-diynes: an approach for divergent assembly of functionalized quinolin-2(1H)-ones

Daixiang Chen et al. Front Chem. .

Abstract

The first photocatalytic trichloromethyl radical-triggered annulative reactions of amide-linked 1,7-diynes with polyhalomethanes were established for the flexible assembly of functionalized quinolin-2(1H)-ones with generally acceptable yields. With the installation of the aryl group (R1) into the alkynyl moiety, C-center radical-initiated Kharasch-type addition/nucleophilic substitution/elimination cascade to produce quinolin-2(1H)-ones-incorporating gem-dihaloalkene, whereas three examples of polyhalogenated quinolin-2(1H)-ones were afforded when amide-linked 1,7-diynes bearing two terminal alkyne units were subjected to BrCX3 by exploiting dry acetonitrile as a solvent.

Keywords: 1,7-diynes; Kharasch addition; annulative reactions; photoinduced; quinolin-2(1H)-ones.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

FIGURE 1
FIGURE 1
Selected examples of natural products and bioactive molecules containing quinolin-2(1H)-ones.
SCHEME 1
SCHEME 1
Methods for synthesizing gem-dihaloalkenes (A) and tandem annulation of 1,7-diynes (B-C).
SCHEME 2
SCHEME 2
Substrate scope for synthesizing product 3
SCHEME 3
SCHEME 3
Synthesis of polyhalogenated quinolin-2(1H)-one 4a (A) and 4b-4c (B).
SCHEME 4
SCHEME 4
Scaled-up preparation (A) and product transformation (B).
SCHEME 5
SCHEME 5
Mechanistic experiments (A-C).
FIGURE 2
FIGURE 2
Stern–Volmer analysis for fac-Ir(ppy)3 with 1a and BrCCl3 2a.
SCHEME 6
SCHEME 6
Plausible reaction pathway for forming 3 and 4.
See this image and copyright information in PMC

References

    1. Bacauanu V., Cardinal S., Yamauchi M., Kondo M., Fernandez D. F., Remy R., et al. (2018). Metallaphotoredox difluoromethylation of aryl bromides. Angew. Chem. Int. Ed. 57, 12543–12548. 10.1002/anie.201807629 - DOI - PMC - PubMed
    1. Bach T., Bergmann H., Grosch B., Harms K. (2002). Highly enantioselective intra- and intermolecular [2 + 2] photocycloaddition reactions of 2-quinolones mediated by a chiral lactam host: host-guest interactions, product configuration, and the origin of the stereoselectivity in solution. J. Am. Chem. Soc. 124, 7982–7990. 10.1021/ja0122288 - DOI - PubMed
    1. Berrino R., Cacchi S., Fabrizi G., Goggiamani A. (2012). 4-Aryl-2-quinolones from 3,3-diarylacrylamides through intramolecular copper-catalyzed C–H functionalization/C–N bond formation. J. Org. Chem. 77, 2537–2542. 10.1021/jo202427m - DOI - PubMed
    1. Chelucci G. (2012). Synthesis and metal-catalyzed reactions of gem-dihalovinyl systems. Chem. Rev. 112, 1344–1462. 10.1021/cr200165q - DOI - PubMed
    1. Chintawar C.-C., Mane M.-V., Tathe A.-G., Biswas S., Patil N.-T. (2019). Gold-catalyzed cycloisomerization of pyridine-bridged 1,8-diynes: an expedient access to luminescent cycl[3.2.2]azines. Org. Lett. 21, 7109–7113. 10.1021/acs.orglett.9b02677 - DOI - PubMed