AI Article Synopsis
- A new metal-free method allows for the creation of α-arylidene cyclopenta[]indoles through the use of phosphine-catalyzed (3 + 2) annulation involving α,β-ynones and 3-nitroindoles.
- This approach successfully demonstrates the rearomatisation of the indole structure during the process for the first time.
- The technique was also applied to synthesize the antimalarial compound bruceolline E.
Article Abstract
We describe a metal-free strategy to access various α-arylidene cyclopenta[]indoles phosphine-catalysed (3 + 2) annulation of α,β-ynones and 3-nitroindoles. For the first time, the rearomatisation of the indole nucleus was observed in such an annulative transformation. The method was extended to the synthesis of an antimalarial natural product, bruceolline E.
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| http://dx.doi.org/10.1039/d2ob02180c | DOI Listing |
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