Facile Synthesis of 2H-Benzo[h]Chromenes via an Arylamine-Catalyzed Mannich Cyclization Cascade Reaction
作者:Yueteng Zhang、Peng Ji、Xiang Meng、Feng Gao、Fanxun Zeng、Wei Wang
DOI:10.3390/molecules26123617
日期:——
Mannich-cyclization cascade reaction was developed for facilesynthesis of substituted 2H-benzo[h]chromenes. The notable feature of the process included the efficient generation of ortho-quinone methides (o-QMs) catalyzed by a simple aniline. The mild reaction conditions allowed for a broad spectrum of 1- and 2-naphthols and trans-cinnamaldehydes to engage in the cascade sequence with high efficiency.
开发了一种简单的芳胺催化曼尼希环化级联反应,用于轻松合成取代的 2 H-苯并[ h ]色烯。该过程的显着特点包括在简单的苯胺催化下有效生成邻醌甲基化物( o -QM)。温和的反应条件允许广谱的1-和2-萘酚以及反式肉桂醛高效地参与级联序列。
An efficient and simple method for synthesis of 2,2-disubstituted-2H-chromenes by condensation of a phenol with a 1,1-disubstituted propargyl alcohol using BF3·Et2O as the catalyst
An efficient and simple method for the synthesis of 2,2-disubstituted-2H-chromenes by one-step cyclocondensation of a phenol with a variety of 1,1-disubstituted propargyl alcohols using BF3·Et2O as the catalyst is described.
Boronic acid/Brønsted acid co-catalyst systems for the synthesis of 2H-chromenes from phenols and α,β-unsaturated carbonyls
作者:Victoria Dimakos、Tishaan Singh、Mark S. Taylor
DOI:10.1039/c6ob01026a
日期:——
Protocols for the synthesis of substituted 2H-chromenes from α,β-unsaturated carbonyls and phenols are described. Optimal combinations of arylboronic acids and Brønsted acids have been identified, such that both can be employed in catalytic quantities to accelerate these condensations. The method has been used to synthesize a variety of substituted 2H-chromenes, as well as photochromic naphthopyrans
ReCl(CO)5-catalyzed cyclocondensation of phenols with 2-methyl-3-butyn-2-ol to afford 2,2-dimethyl-2H-chromenes
作者:Hanxiang Zeng、Jia Ju、Ruimao Hua
DOI:10.1016/j.tetlet.2011.05.093
日期:2011.7
A direct one-pot route for the synthesis of 2,2-dimethyl-2H-chromenes by Re(CO)5Cl-catalyzed cyclocondensation of phenols with 2-methyl-3-butyn-2-ol has been developed. The easy availability of starting materials, mild reaction conditions, high atom-efficiency, and the use of a recoverable catalyst are advantages of this procedure.
A Novel Method for the Synthesis of Substituted Benzochromenes by Ethylenediamine Diacetate-Catalyzed Cyclizations of Naphthalenols toα,β-Unsaturated Aldehydes. Concise Synthesis of the Natural Products Lapachenole, Dihydrolapachenole, and Mollugin
作者:Yong Rok Lee、Yun Mi Kim
DOI:10.1002/hlca.200790247
日期:2007.12
benzochromenes was developed starting from naphthalenols and α,β-unsaturated aldehydes in the presence of ethylenediamine diacetate. This methodology was applied for the total synthesis of the biologically important natural products lapachenole, dihydrolapachenole, and mollugin with a benzochromene moiety.