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Updated: Jun 26, 2026
Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Stereoselective hydrogenation of aromatic alkynes using water, triethylsilane, or methanol, mediated and catalyzed by
Rigoberto Barrios-Francisco1, Juventino J García
1Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Mexico D. F. 04510, Mexico.
Abstract:
The use of complexes of the type [(P-P)Ni(eta(2)-C,C-alkyne)] (P-P = 1,2-bis(di-isopropyl-phosphinoethane or 1,2-bis(diterbutylphosphino-ethane) in the presence of water, triethylsilane/water, or methanol as hydrogen sources yields the selective production of E- or Z- aromatic alkenes from the corresponding alkynes. For instance, in the case of diphenylacetylene (dpa) and water, a metal-mediated process was found to yield trans-stilbene stoichiometrically, whereas in the case of triethylsilane/water and methanol, a catalytic system (1% mol) was found. The catalytic systems gave >95% conversion to cis- or trans-stilbene, respectively. The use of a variety of substituents on the aromatic ring was also assessed. Deuterium-labeling studies using D(2)O allowed the confirmation of water as the hydrogen source for the alkyne reduction.
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