PMID- 36507773 OWN - NLM STAT- MEDLINE DCOM- 20221222 LR - 20221222 IS - 1520-5126 (Electronic) IS - 0002-7863 (Linking) VI - 144 IP - 50 DP - 2022 Dec 21 TI - Mechanical Bond-Assisted Full-Spectrum Investigation of Radical Interactions. PG - 23168-23178 LID - 10.1021/jacs.2c10882 [doi] AB - Molecular recognition, based on noncovalent bonding interactions, plays a central role in directing supramolecular phenomena in both chemical and biological environments. The identification and investigation of weakly associated recognition motifs, however, remains a major challenge, especially when the motifs are interlinked with and obscured by other robust binding modes in complicated systems. For example, although the host-guest recognition between the radical cations of both cyclobis(paraquat-p-phenylene) (CBPQT) and 4,4'-bipyridinium (BIPY) salts has been thoroughly investigated, the question of whether other binding modes exist between these two positively charged entities is the subject of some debate because of the complexity and dynamic nature of this supramolecular system. In order to address this conundrum, we have synthesized a [2]catenane horizontal line formed by mechanical interlocking between CBPQT and another BIPY-containing ring horizontal line which enhances the weak interactions between components and reduces significantly the complexity of the system for easier characterization. By employing this [2]catenane as a model compound, we have performed a full-spectrum investigation of radical interactions and revealed unambiguously a total of three possible binding modes between CBPQT and BIPY horizontal line to be specific, a bisradical tetracationic, a trisradical tricationic, and a bisradical dicationic association horizontal line as demonstrated by various methods of characterization including UV/vis/NIR, EPR, and NMR spectroscopies, electrochemical measurements and X-ray crystallography. The two newly discovered bisradical binding modes have potential applications in the construction of self-assembled materials and in mediating supramolecular catalysis. The mechanical bond-assisted approach used in this research is broadly applicable to investigating noncovalent bonding interactions. FAU - Jiao, Yang AU - Jiao Y AUID- ORCID: 0000-0002-8437-0038 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Mao, Haochuan AU - Mao H AUID- ORCID: 0000-0001-8742-089X AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. AD - Institute for Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Qiu, Yunyan AU - Qiu Y AUID- ORCID: 0000-0001-9279-4714 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Wu, Guangcheng AU - Wu G AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Chen, Hongliang AU - Chen H AUID- ORCID: 0000-0002-4442-7984 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. AD - Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310027, China. AD - ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China. FAU - Zhang, Long AU - Zhang L AUID- ORCID: 0000-0002-4631-158X AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Han, Han AU - Han H AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Li, Xuesong AU - Li X AUID- ORCID: 0000-0002-2794-8390 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Zhao, Xingang AU - Zhao X AUID- ORCID: 0000-0001-5852-9757 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Tang, Chun AU - Tang C AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Chen, Xiao-Yang AU - Chen XY AUID- ORCID: 0000-0003-3449-4136 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Feng, Yuanning AU - Feng Y AUID- ORCID: 0000-0002-8832-0767 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Stern, Charlotte L AU - Stern CL AUID- ORCID: 0000-0002-9491-289X AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Wasielewski, Michael R AU - Wasielewski MR AUID- ORCID: 0000-0003-2920-5440 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. AD - Institute for Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. FAU - Stoddart, J Fraser AU - Stoddart JF AUID- ORCID: 0000-0003-3161-3697 AD - Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States. AD - Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310027, China. AD - ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China. AD - School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't PT - Research Support, U.S. Gov't, Non-P.H.S. DEP - 20221212 PL - United States TA - J Am Chem Soc JT - Journal of the American Chemical Society JID - 7503056 RN - 0 (Cations) SB - IM MH - *Magnetic Resonance Spectroscopy MH - Cations/chemistry MH - Crystallography, X-Ray EDAT- 2022/12/13 06:00 MHDA- 2022/12/23 06:00 CRDT- 2022/12/12 11:50 PHST- 2022/12/13 06:00 [pubmed] PHST- 2022/12/23 06:00 [medline] PHST- 2022/12/12 11:50 [entrez] AID - 10.1021/jacs.2c10882 [doi] PST - ppublish SO - J Am Chem Soc. 2022 Dec 21;144(50):23168-23178. doi: 10.1021/jacs.2c10882. Epub 2022 Dec 12.