A multistep continuous flow synthesis machine for the preparation of pyrazoles via a metal-free amine-redox process

Jian-Siang Poh; Duncan L Browne; Steven V Ley

doi:10.1039/c5re00082c

A multistep continuous flow synthesis machine for the preparation of pyrazoles via a metal-free amine-redox process

React Chem Eng. 2016 Feb 3;1(1):101-105. doi: 10.1039/c5re00082c. Epub 2016 Jan 7.

Authors

Jian-Siang Poh¹, Duncan L Browne², Steven V Ley¹

Affiliations

¹ Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge , CB2 1EW , UK.
² Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge , CB2 1EW , UK ; School of Chemistry , Cardiff University , Main Building, Park Place , CF10 3AT , UK . Email: dlbrowne@cardiff.ac.uk.

Abstract

A versatile multistep continuous flow setup is reported for the four-step conversion of anilines into pyrazole products. The synthesis machine incorporates the use of amine-redox chemistry through diazotization and a metal-free vitamin C mediated reduction. The machine can be used for the synthesis of an array of analogues or the scale up of an individual target.