Facile Installation of 2-Reverse Prenyl Functionality into Indoles by a Tandem N-Alkylation-Aza-Cope Rearrangement Reaction and Its Application in Synthesis was written by Chen, Xiaobei;Fan, Huaqiang;Zhang, Shilei;Yu, Chenguang;Wang, Wei. And the article was included in Chemistry – A European Journal in 2016.Reference of 827-01-0 This article mentions the following:
An unprecedented tandem N-alkylation-ionic aza-Cope (or Claisen) rearrangement-hydrolysis reaction of readily available indolyl bromides with enamines is described. Due to the complicated nature of the two processes, an operationally simple N-alkylation and subsequent microwave-irradiated ionic aza-Cope rearrangement-hydrolysis process was uncovered. The tandem reaction serves as a powerful approach to the preparation of synthetically and biol. important, but challenging, 2-reverse quaternary-centered prenylated indoles with high efficiency. Notably, unusual nonaromatic 3-methylene-2,3-dihydro-1H-indole architectures, instead of aromatic indoles, are produced. Furthermore, the aza-Cope rearrangement reaction proceeds highly regioselectively to give the quaternary-centered reverse prenyl functionality, which often produces a mixture of two regioisomers by reported methods. The synthetic value of the resulting nonaromatic 3-methylene-2,3-dihydro-1H-indole architectures was demonstrated as versatile building blocks in the efficient synthesis of structurally diverse 2-reverse prenylated indoles, such as indolines, indole-fused sultams and lactams, and the natural product bruceolline D. In the experiment, the researchers used many compounds, for example, 5-Chloroindole-3-carboxaldehyde (cas: 827-01-0Reference of 827-01-0).
5-Chloroindole-3-carboxaldehyde (cas: 827-01-0) belongs to indole derivatives. Indole exists overwhelmingly in the 1H-indole form as do other simple indoles. Due to this activity, the indole ring system has become an important component or intermediate in the synthesis of heterocycles.Reference of 827-01-0
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Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles