. 2020 Mar 16;25(6):1349. doi: 10.3390/molecules25061349
© 2020 by the authors.
Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
Scheme 23.
Bäckvall’s and Rueping’s cycloisomerizations.