Asahara Haruyasu, Hiraishi Minami, Nishiwaki Nagatoshi
School of Environmental Science and Engineering, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan.
Research Center for Molecular Design, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan.
Beilstein J Org Chem. 2020 Jul 22;16:1830-1836. doi: 10.3762/bjoc.16.150. eCollection 2020.
β-Nitrostyrenes underwent a Diels-Alder reaction with Danishefsky's diene to afford cyclohexenes together with the corresponding hydrolyzed products, 3-arylated-5-methoxy-4-nitrocyclohexanones. When the reaction was conducted in the presence of water, the cyclohexenes were efficiently hydrolyzed into cyclohexanones. Subsequent aromatization by heating the cyclohexanone with a catalytic amount of iodine in dimethyl sulfoxide gave 3-arylated-4-nitrophenols. The reaction of nitrostyrenes with Danishefsky's diene could be conducted in one pot to directly afford the corresponding nitrophenols. Moreover, a heteroaryl group, e.g., a thienyl group could be introduced into the nitrophenol framework.
β-硝基苯乙烯与丹尼谢夫斯基双烯发生狄尔斯-阿尔德反应，生成环己烯以及相应的水解产物3-芳基-5-甲氧基-4-硝基环己酮。当反应在水存在下进行时，环己烯能有效地水解为环己酮。随后，在二甲基亚砜中用催化量的碘加热环己酮进行芳构化反应，得到3-芳基-4-硝基苯酚。硝基苯乙烯与丹尼谢夫斯基双烯的反应可以一锅法进行，直接得到相应的硝基苯酚。此外，杂芳基，例如噻吩基，可以引入到硝基苯酚骨架中。
