Kinetic study of the microflow synthesis of 4-hydroxyquinoline in supercritical ethanol

Kinetic study of the microflow synthesis of 4-hydroxyquinoline in supercritical ethanol Article history: Supercritical ethanol was used as a solvent for the thermal cyclization of ethyl 3-(phenylimino)-butanoate Received 14 September 2015 to 2-methyl-4-hydroxyquinoline; the reaction is of great importance in pharmaceutical and color indus- Received in revised form 30 March 2016 tries but conventionally needs specific solvents with high boiling points. The mechanism and the kinetics Accepted 30 March 2016 were studied with a microreactor by measuring the yield of the product at various temperatures up to Available online 30 March 2016 ◦ ◦ 350 C. The reaction in ethanol completed in 27 s at 350 C and 10.0 MPa giving the quinoline in 97% GC yield, although it required higher temperature than that in acetonitrile. The results were explained Keywords: by the mechanism consisting of the two steps: (i) a reversible elimination of ethanol from the reactant Supercritical alcohol yielding ketene intermediate followed by (ii) an irreversible ring closure into the quinoline. On the basis The Conrad-Limpach thermal cyclization of the reaction mechanism, the rate constant and the activation energy were determined from the yield- High-temperature and high-pressure ◦ −3 time profiles measured at temperatures of 300–350 C and a constant ethanol density of 0.11 g cm . The http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Supercritical Fluids Elsevier

Kinetic study of the microflow synthesis of 4-hydroxyquinoline in supercritical ethanol

Loading next page...
 
/lp/elsevier/kinetic-study-of-the-microflow-synthesis-of-4-hydroxyquinoline-in-RJnTPOe6bj
Publisher
Elsevier
Copyright
Copyright © 2016 Elsevier B.V.
ISSN
0896-8446
eISSN
1872-8162
D.O.I.
10.1016/j.supflu.2016.03.029
Publisher site
See Article on Publisher Site

Abstract

Article history: Supercritical ethanol was used as a solvent for the thermal cyclization of ethyl 3-(phenylimino)-butanoate Received 14 September 2015 to 2-methyl-4-hydroxyquinoline; the reaction is of great importance in pharmaceutical and color indus- Received in revised form 30 March 2016 tries but conventionally needs specific solvents with high boiling points. The mechanism and the kinetics Accepted 30 March 2016 were studied with a microreactor by measuring the yield of the product at various temperatures up to Available online 30 March 2016 ◦ ◦ 350 C. The reaction in ethanol completed in 27 s at 350 C and 10.0 MPa giving the quinoline in 97% GC yield, although it required higher temperature than that in acetonitrile. The results were explained Keywords: by the mechanism consisting of the two steps: (i) a reversible elimination of ethanol from the reactant Supercritical alcohol yielding ketene intermediate followed by (ii) an irreversible ring closure into the quinoline. On the basis The Conrad-Limpach thermal cyclization of the reaction mechanism, the rate constant and the activation energy were determined from the yield- High-temperature and high-pressure ◦ −3 time profiles measured at temperatures of 300–350 C and a constant ethanol density of 0.11 g cm . The

Journal

The Journal of Supercritical FluidsElsevier

Published: Aug 1, 2016

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • No expiration
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches

$49/month

Start Free Trial

14-day Free Trial

Best Deal — 39% off

Annual Plan

  • All the features of the Professional Plan, but for 39% off!
  • Billed annually
  • No expiration
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.

$588

$360/year

billed annually
Start Free Trial

14-day Free Trial