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Updated: Aug 12, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Nucleophilic addition to the ethynyl group in ethynylestradiol catalyzed by crown ether-copper (1) iodide
Abstract:
A new and convenient synthetic route to acetylation of estrogens is described. Benzo-15-crown-5 and cuprous iodide-mixed catalyst catalyzed the nucleophilic addition of 2,4-dibromoethynylestradiol, resulting in the formation of a new compound, 2,4-dibromo-17 alpha-acetylestradiol, of which the structure was characterized by infrared, UV, 1H nuclear magnetic resonance, mass spectra, and elemental analysis. It was found that the yield of this approach is much higher than that obtained in the hydration of usual acetylenic compounds.
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