. 2016 Jun 8;55(31):8928–8932. doi: 10.1002/anie.201603175
© 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made.
Scheme 5.
Mechanistic possibilities.