Cesium Carbonate Promoted N-Alkylation of Indoles

Abstract

The N-alkylation of indoles with alkyl halides and epoxides, using cesium carbonate as the base in DMPU, is reported.

Key words

cesium carbonate - indoles - alkylation - epoxides - alkyl halides

References

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9

Using n-butyllithium as the base in THF as in ref. 2 resulted in a slow but clean conversion to product (24% conversion at reflux for 18 h). However, if DMPU was used as solvent, then the product was formed at r.t. over 48 h.

12

The products exhibited satisfactory ¹H NMR spectra.