Flow synthesis using gaseous ammonia in a Teflon AF-2400 tube-in-tube reactor: Paal–Knorr pyrrole formation and gas concentration measurement by inline flow titration

Cranwell, P. ORCID: https://orcid.org/0000-0001-7156-5576, O'Brien, M., Browne, D.L., Koos, P., Polyzos, A., Peña-López, M. and Ley, S.V. (2012) Flow synthesis using gaseous ammonia in a Teflon AF-2400 tube-in-tube reactor: Paal–Knorr pyrrole formation and gas concentration measurement by inline flow titration. Organic & Biomolecular Chemistry, 10. pp. 5774-5779. ISSN 1477-0520 doi: 10.1039/c2ob25407g

Abstract/Summary

Using a simple and accessible Teflon AF-2400 based tube-intube reactor, a series of pyrroles were synthesised in flow using the Paal–Knorr reaction of 1,4-diketones with gaseous ammonia. An inline flow titration technique allowed measurement of the ammonia concentration and its relationship to residence time and temperature.