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Abstract The one‐step synthesis of tetra‐substituted benzenes was accomplished via gold‐catalyzed diyne‐ene annulation. Distinguished from prior modification methods, this novel strategy undergoes formal [3+3] cyclization, producing polysubstituted benzenes with exceptional efficiency. The critical factor enabling this transformation was the introduction of amides, which were reported for the first time in gold catalysis as covalent nucleophilic co‐catalysts. This interesting protocol not only offers a new strategy to achieve functional benzenes with high efficiency, but also enlightens potential new reaction pathways within gold‐catalyzed alkyne activation processes.
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The molecular structure and curious motions in 1,1-difluorosilacyclopent-3-ene and silacyclopent-3-ene as determined by microwave spectroscopy and quantum chemical calculations
The molecules 1,1-difluorosilacyclopent-3-ene (3SiCPF 2 ) and silacyclopent-3-ene (3SiCP) have been synthesized and studied using chirped pulse, Fourier transform microwave (CP-FTMW) spectroscopy. For 3SiCP this is the first ever microwave study of the molecule and, for 3SiCPF 2 , the spectra reported in this work have been combined with that of previous work in a global fit. The spectra of each contain splitting which has been fit using a Hamiltonian consisting of semirigid and Coriolis coupling parameters. A refit of the original 3SiCPF 2 work was also carried out. All fits and approaches are reported. Analyses of the spectra provide evidence that the molecule is planar which is in agreement with the high-level calculations, but the source of the splitting in the spectra has not been determined.
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- PAR ID:
- 10346015
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 24
- Issue:
- 4
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 2454 to 2464
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d1cp04286f
