Improved Synthesis of Dialkylaminopyrrolines

Abstract

The literature synthesis of 5-dialkylamino-3,4-dihydro-2H-pyrroles from 5-methoxy-3,4-dihydro-2H-pyrrole has been much improved. In initial assays, the pyrrolinium salts obtained on alkylation of the dibutylaminoamidine are excellent “naked halide” catalysts.

Keywords:

• Dialkylaminopyrrolines
• Amidininium salts
• Naked halide catalysts
• Phase transfer catalysis
• Chloroformates

Acknowledgments

We thank PPG Industries for partial support of this research and Dr. C. Kreutzberger of PPG for advice and arranging the thermogravimetric analysis.