Organic & Biomolecular Chemistry
Paper
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Experimental section
General information
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All commercial materials were used as received unless other-
wise noted. Commercially available chemicals were obtained
from Energy Chemical, TCI, Alfa Aesar, and J&K. 1H NMR
spectra were recorded at 400 MHz and 600 MHz using TMS as
an internal standard, and 13C NMR spectra were recorded at
100 MHz, 125 MHz and 150 MHz using TMS as an internal
standard. The multiplicities are reported as follows: singlet (s),
doublet (d), doublet of doublets (dd), multiplet (m), triplet (t)
and broad resonances (br). The mass spectroscopy data of the
products were collected on an HRMS-TOF instrument.
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General procedure for the synthesis of 3. A mixture of 1H-
indole (1a, 117.0 mg, 1.0 mmol), ethynylbenzene (2a,
204.2 mg, 2.0 mmol) and B(C6F5)3 (25.6 mg, 0.05 mmol) was
heated at 60 °C for 6 hours. After the reaction was completed,
the residue was purified by chromatography on silica gel
(n-hexane/EtOAc = 20 : 1) to obtain the product 3a (142.9 mg,
85%) as a white solid. 3b–w were synthesized in a similar way.
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Conflicts of interest
There are no conflicts to declare.
Acknowledgements
We thank the National Natural Science Foundation of China
(no. 21676253 and 21706234) for financial support.
Notes and references
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