Reaction of phosphinyl nitrosoalkenes with electron-rich heterocycles

Abstract

Here we described the behavior of phosphinyl nitrosoalkenes with indole, pyrrole and 2,5-dimethylpyrrole. 3-Substituted indoles have been prepared through the reaction of nitrosoalkenes with indole. The reaction of phosphinyl nitrosoalkenes with pyrrole leads to the formation of 2-substituted pyrroles, while the behavior of 2,5-dimethylpyrrole with these nitrosoalkenes affords bicyclic 1,2-oxazines.

GRAPHICAL ABSTRACT

Keywords:

• [4 + 2] cycloaddition
• 2,5-dimethylpyrrole
• electrophilic aromatic substitution
• indole
• phosphinyl nitrosoalkenes
• pyrrole

Acknowledgements

The authors thank Ministerio de Economía, Industria y Competitividad (MINECO, Madrid CTQ-2015-67871R) and Departamento de Educación Universidades e Investigación of Gobierno Vasco (GV, IT 992-16) for supporting this work. UPV/EHU–SGIker technical support for HRMS and NMR spectra (MCINN, GV/EJ, and European Social Fund) is also gratefully acknowledged.