Protonation of Diarylacetylenes in Superacid HSO<sub>3</sub>F and Their Oxidation in the HSO<sub>3</sub>F/PbO<sub>2</sub>System: One-Pot Synthesis of Polysubstituted Naphthalenes
作者:Aleksander V. Vasilyev、Andrey O. Shchukin、Stéphane Walspurger、Jean Sommer
DOI:10.1002/ejoc.200800548
日期:2008.9
In the superacid HSO3F, diarylacetylenes bearing one electron-withdrawing group (NO2, CN, COMe, CO2Me) in each arene ring form stable ions, protonated at these groups. Oxidation of such diarylacetylenes in the HSO3F/PbO2 system at –75 to –50 °C over 2–2.5 h, followed by quenching of the reaction mixture with hydrochloric (or hydrobromic) acid at –60 to 25 °C, resulted in the formation of (E,E)-1,4-dichloro
在超强酸 HSO3F 中,每个芳烃环中带有一个吸电子基团(NO2、CN、COMe、CO2Me)的二芳基乙炔形成稳定的离子,并在这些基团上质子化。在 HSO3F/PbO2 系统中在 –75 至 –50 °C 下氧化此类二芳基乙炔 2–2.5 小时,然后在 –60 至 25 °C 下用盐酸(或氢溴酸)淬灭反应混合物,导致形成(E,E)-1,4-二氯(或二溴)-1,2,3,4-四芳基丁-1,3-二烯。这些丁二烯在室温下自发地进行电环转化为多取代萘。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)