Issue 1, 2015

Accelerated Hantzsch electrospray synthesis with temporal control of reaction intermediates

Abstract

Complex chemical reactions can occur in electrosprayed droplets on the millisecond time scale. The Hantzsch synthesis of 1,4-dihydropyridines was studied in this way using on-line mass spectral analysis to optimize conditions and characterize the product mixture. Changing the distance between the nanospray source and the MS inlet allowed exploration of reaction progress as a function of droplet time-of-flight. Desolvation of the charged microdroplets is associated with transformation from starting material to intermediates and eventually to product as the distance is increased. Results of the on-line experiments require a termination step that discontinuously completes the desolvation process and allows the generated gaseous ions to be used to characterize the state of the system at a particular time. The intermediates seen correspond to those known to occur in the bulk solution-phase reaction. Off-line collection of the sprayed reaction mixture allowed the recovery of 250 mg h−1 of desired reaction product from a single sprayer, permitting characterization by NMR and other standard methods. A thin film version of the accelerated reaction is described and it could be controlled through the temperature of the collection surface.

Graphical abstract: Accelerated Hantzsch electrospray synthesis with temporal control of reaction intermediates

Supplementary files

Article information

Article type
Edge Article
Submitted
11 Aug 2014
Accepted
28 Aug 2014
First published
09 Sep 2014
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY-NC license

Chem. Sci., 2015,6, 397-401

Author version available

Accelerated Hantzsch electrospray synthesis with temporal control of reaction intermediates

R. M. Bain, C. J. Pulliam and R. G. Cooks, Chem. Sci., 2015, 6, 397 DOI: 10.1039/C4SC02436B

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements