1. Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland, http://www.gruetzmacher.ethz.ch
2. Current address: The Weizmann Institute of Science, Department for Organic Chemistry, 76100 Rehovot, Israel
3. Lehn Institute of Functional Materials (LIFM), Sun Yat‐Sen University, 510275 Guangzhou, China