. 2018 May 14;57(24):7181–7185. doi: 10.1002/anie.201802256
© 2018 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Scheme 7.
Initial cyclization attempts.