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The styryl dehydro-Diels–Alder reaction with a conjugated diyne is reported. While typical alkyne–styrene condensation requires elevated temperatures (>160 °C), the application of a conjugated diyne allowed for effective transformation under milder conditions (80 °C). The thermally stable triazole–gold (TA–Au) catalyst further improved the reaction yields (up to 95%), producing the desired alkynyl–naphthalene in a single step with molecular oxygen as the oxidant. Sequential alkyne activation resulted in various polyaromatic hydrocarbons (PAHs) in excellent yields, highlighting the efficiency of this new strategy for the preparation of PAHs with good functional group tolerance and structural diversity.
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This content will become publicly available on October 1, 2026
Expanding tricoordinate Au(I) complexes for efficient carbofunctionalization of alkynes to benzo-fused N-heterocycles and imines
Gold-catalyzed activation of alkynes towards functional molecules remains an interesting endeavor with industrial potential, yet stable, efficient catalysts are needed. Here, we report a shelf-stable tricoordinate Au(I) catalyst for the cyclization of anilino-alkyne derivatives to form C2-substituted indoles and other benzo-fused Nheterocycles. We also report the use of this Au(I) catalyst for intermolecular hydroamination of ethynylbenzene and diphenylacetylene with various aniline derivatives, forming imines. The distorted geometry of Au(I) complexes facilitates alkyne activation and demonstrates functional group tolerance of the catalyst under mild conditions. We expand the scope of previously synthesized benzo-fused N-heterocycles and demonstrate potential for tricoordinate complexes in catalytic systems.
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- Award ID(s):
- 2203559
- PAR ID:
- 10635353
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of Catalysis
- Volume:
- 450
- Issue:
- C
- ISSN:
- 0021-9517
- Page Range / eLocation ID:
- 116317
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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