Editing Polycatenane

{{Short description|Mechanically interlocked molecular architecture}}
[[File:Polycatenane (cropped).jpg|thumb|Polycatenane model.<ref name=":2">{{Cite journal |last1=Wu |first1=Qiong |last2=Rauscher |first2=Phillip M. |last3=Lang |first3=Xiaolong |last4=Wojtecki |first4=Rudy J. |last5=de Pablo |first5=Juan J. |last6=Hore |first6=Michael J. A. |last7=Rowan |first7=Stuart J. |date=2017-12-15 |title=Poly[ n ]catenanes: Synthesis of molecular interlocked chains |journal=Science |language=en |volume=358 |issue=6369 |pages=1434–1439 |doi=10.1126/science.aap7675 |pmid=29192134 |bibcode=2017Sci...358.1434W |s2cid=667951 |issn=0036-8075|doi-access=free }}</ref>]]
A '''polycatenane''' is a chemical substance that, like [[polymer]]s, is chemically constituted by a large number of units.<ref name=":0">{{cite journal | author = Z.Niu and Harry.W. Gibson | title = Polycatenanes | year = 2009 | journal = [[Chem. Rev.]] | volume = 109 | issue = 11 | pages = 6024–6046 |doi= 10.1021/cr900002h| pmid = 19670889 }}</ref> These units are made up of concatenated rings into a chain-like structure.

It consists of mechanically linked [[catenane]]<ref>{{Cite journal |last1=Gil-Ramírez |first1=Guzmán |last2=Leigh |first2=David A. |last3=Stephens |first3=Alexander J. |date=2015-05-07 |title=Catenanes: Fifty Years of Molecular Links |url=http://dx.doi.org/10.1002/anie.201411619 |journal=Angewandte Chemie International Edition |volume=54 |issue=21 |pages=6110–6150 |doi=10.1002/anie.201411619 |pmid=25951013 |pmc=4515087 |issn=1433-7851}}</ref> structures, via topological [[Hopf link]]s, resulting in a higher dimensionality than the repeating unit.<ref>{{Cite book |last=Flapan |first=Erica |url=https://www.cambridge.org/core/books/when-topology-meets-chemistry/1B5638674BE0A88BB598C78E18D831DA |title=When Topology Meets Chemistry: A Topological Look at Molecular Chirality |date=2000 |publisher=Cambridge University Press |isbn=978-0-521-66254-3 |series=Outlooks |location=Cambridge |doi=10.1017/cbo9780511626272}}</ref><ref>{{Cite journal |last1=Carlucci |first1=Lucia |last2=Ciani |first2=Gianfranco |last3=Proserpio |first3=Davide M. |date=November 2003 |title=Polycatenation, polythreading and polyknotting in coordination network chemistry |url=http://dx.doi.org/10.1016/s0010-8545(03)00126-7 |journal=Coordination Chemistry Reviews |volume=246 |issue=1–2 |pages=247–289 |doi=10.1016/s0010-8545(03)00126-7 |issn=0010-8545|url-access=subscription }}</ref> They are a class of catenanes where the number of [[macrocycle]]s is greater than two and as catenanes they belong to the big family of [[Mechanically interlocked molecular architectures|mechanically interlocked molecular architectures (MIMAs)]].<ref>{{Cite book |last1=Davis |first1=Frank |title=Macrocycles: construction, chemistry, and nanotechnology applications |last2=Higson |first2=Séamus |date=2011 |publisher=Wiley |isbn=978-1-119-98993-6 |location=Chichester}}</ref><ref name=":1">{{Cite journal |last1=Fang |first1=Lei |last2=Olson |first2=Mark A. |last3=Benítez |first3=Diego |last4=Tkatchouk |first4=Ekaterina |last5=Goddard III |first5=William A. |last6=Stoddart |first6=J. Fraser |date=2010 |title=Mechanically bonded macromolecules |url=http://xlink.rsc.org/?DOI=B917901A |journal=Chem. Soc. Rev. |language=en |volume=39 |issue=1 |pages=17–29 |doi=10.1039/B917901A |issn=0306-0012 |pmid=20023833}}</ref><ref>{{Cite journal |last1=Amabilino |first1=David B. |last2=Stoddart |first2=J. Fraser |date=December 1995 |title=Interlocked and Intertwined Structures and Superstructures |url=http://dx.doi.org/10.1021/cr00040a005 |journal=Chemical Reviews |volume=95 |issue=8 |pages=2725–2828 |doi=10.1021/cr00040a005 |issn=0009-2665|url-access=subscription }}</ref>

[[File:Catenane mobility.tif|thumb|Reciprocal degree of motion of polycatenanes rings.]] The characteristic feature of a polycatenane compound, that distinguishes it from other polymers, is the presence of mechanical bonds in addition to covalent bonds.<ref name=":1" /><ref>{{Cite journal |last=Stoddart |first=J. Fraser |date=2009 |title=The chemistry of the mechanical bond |url=http://xlink.rsc.org/?DOI=b819333a |journal=Chemical Society Reviews |language=en |volume=38 |issue=6 |pages=1802–1820 |doi=10.1039/b819333a |issn=0306-0012 |pmid=19587969|url-access=subscription }}</ref><ref>{{Cite book |last1=Bruns |first1=Carson J. |title=The nature of the mechanical bond: from molecules to machines |last2=Stoddart |first2=J. F. |last3=Stoddart |first3=James Fraser |date=2017 |publisher=John Wiley & Sons |isbn=978-1-119-04400-0 |location=Hoboken, New Jersey}}</ref> The rings in this chain-like structure can be separated only when high energy is provided to break at least a covalent bond of the macrocycle. [''n'']-Catenanes (for large n), which consist solely of the mechanically interlocked cyclic components, can be viewed as “optimized” polycatenanes. The main difference between poly-[''2'']-catenanes and poly-[''n'']-catenanes is the repeating unit, as a monomer is for the polymer.<ref>{{Cite journal |last1=Xing |first1=Hao |last2=Li |first2=Zhandong |last3=Wang |first3=Wenbo |last4=Liu |first4=Peiren |last5=Liu |first5=Junkai |last6=Song |first6=Yu |last7=Wu |first7=Zi Liang |last8=Zhang |first8=Wenke |last9=Huang |first9=Feihe |date=February 2020 |title=Mechanochemistry of an Interlocked Poly[2]catenane: From Single Molecule to Bulk Gel |journal=CCS Chemistry |volume=2 |issue=1 |pages=513–523 |doi=10.31635/ccschem.019.20190043 |s2cid=219164409 |issn=2096-5745|doi-access=free }}</ref><ref name=":2" /><ref>{{Citation |last=Geerts |first=Yves |title=Polycatenanes, Poly[2]catenanes, and Polymeric Catenanes |date=1999-06-24 |url=https://onlinelibrary.wiley.com/doi/10.1002/9783527613724.ch10 |work=Molecular Catenanes, Rotaxanes and Knots |pages=247–276 |editor-last=Sauvage |editor-first=J.-P. |access-date=2023-07-05 |edition=1 |publisher=Wiley |language=en |doi=10.1002/9783527613724.ch10 |isbn=978-3-527-29572-2 |editor2-last=Dietrich-Buchecker |editor2-first=C.|url-access=subscription }}</ref> In the first case the monomer is made of two interlocked rings that repeat continuously in the final polycatenane, while in the latter case there is only one ring that repeat the interlocking process for a large number of times. If the rings of the polycatenane are all of the same type, it can be defined as a homocatenane while if the subunits are different it is defined as heterocatenane.

As a chain, the degree of motion of these structures is very high, greater than the one of a usual polymer, because the rings possess a reciprocal rotational, elongational and rocking motion.<ref name=":2" /> This flexibility is retained even if the macrocycles themselves are very rigid units, because the mobility is given by the ability of the rings to move with respect to each other. This mobility influences the final properties of the material (mechanical, rheological and thermal), and provides a dynamic behavior.<ref name=":6">{{Cite journal |last1=Rauscher |first1=Phillip M. |last2=Schweizer |first2=Kenneth S. |last3=Rowan |first3=Stuart J. |last4=de Pablo |first4=Juan J. |date=2020-06-07 |title=Dynamics of poly[ n ]catenane melts |url=https://pubs.aip.org/jcp/article/152/21/214901/198671/Dynamics-of-poly-n-catenane-melts |journal=The Journal of Chemical Physics |language=en |volume=152 |issue=21 |page=214901 |bibcode=2020JChPh.152u4901R |doi=10.1063/5.0007573 |issn=0021-9606 |pmid=32505155 |s2cid=219537697|doi-access=free }}</ref>

== Classification ==
[[File:Polycatenanes.tif|thumb|Four classes of polycatenanes]]
Depending on the location of the catenane structures in the polymer chain, the polycatenanes can be divided into main-chain polycatenanes and side-chain polycatenanes.<ref name=":0" /><ref name=":1" /><ref name=":5">{{Cite book |title=Encyclopedia of polymeric nanomaterials. Vol. 3: Pm - Z |date=2015 |publisher=Springer-Reference |isbn=978-3-642-29647-5 |location=Heidelberg Berlin |pages=1796–1802}}</ref>

Main-chain polycatenanes are linear catenanes in which the rings are interlocked in a large number of units. They can also be a series of oligomers linked physically even if not interlocked together. The stability of the structure is not only given by mechanical bonds but also hydrogen bonds and π-π interactions between the rings.<ref name=":0" />

On the other hand, the side-chain polycatenanes are polycatenanes with ramifications where more oligomers are connected on the same cycle with respect to the main backbone. This type of catenane is synthesised, functionalising the macrocycles so that there is directionality with the possibility to control the ramification.<ref name=":0" />

There are other types of polycatenanes like the ones based on cyclic polymers, where the macrocyles are interlocked to the cyclic polymers, or the polycatenane networks, where catenanes are interlocked into a net.<ref>{{Cite journal |last1=Semlyen |first1=J. A. |last2=Wood |first2=B. R. |last3=Hodge |first3=P. |date=September 1994 |title=Cyclic polymers: past, present and future |url=https://onlinelibrary.wiley.com/doi/10.1002/pat.1994.220050902 |journal=Polymers for Advanced Technologies |volume=5 |issue=9 |pages=473–478 |doi=10.1002/pat.1994.220050902|url-access=subscription }}</ref><ref>{{Cite journal |last1=Hart |first1=Laura F. |last2=Lenart |first2=William R. |last3=Hertzog |first3=Jerald E. |last4=Oh |first4=Jongwon |last5=Turner |first5=Wilson R. |last6=Dennis |first6=Joseph M. |last7=Rowan |first7=Stuart J. |date=2023-06-07 |title=Doubly Threaded Slide-Ring Polycatenane Networks |url=https://pubs.acs.org/doi/10.1021/jacs.3c02837 |journal=Journal of the American Chemical Society |language=en |volume=145 |issue=22 |pages=12315–12323 |doi=10.1021/jacs.3c02837 |issn=0002-7863 |pmid=37227296 |bibcode=2023JAChS.14512315H |s2cid=258888690|url-access=subscription }}</ref>

=== Catenated nanocages ===
The basic unit of the polycatenane can differ from the relatively simple organic macrocycle. When organic and inorganic building blocks come together, they can form [[coordination cage]]s (or [[macromolecular cages]]) that can interlock with one another to form a polycatenane structure.<ref>{{Cite journal |last1=Frank |first1=Marina |last2=Johnstone |first2=Mark D. |last3=Clever |first3=Guido H. |date=2016-09-26 |title=Interpenetrated Cage Structures |url=https://onlinelibrary.wiley.com/doi/10.1002/chem.201601752 |journal=Chemistry - A European Journal |language=en |volume=22 |issue=40 |pages=14104–14125 |doi=10.1002/chem.201601752 |pmid=27417259|url-access=subscription }}</ref> The mechanism is still unexplored but generally the subunits [[Self-assembly|self-assemble]] into a 0D cage and, in a concerted process, interlock together into a linear or more intricate catenane structure.<ref>{{Cite journal |last1=Constable |first1=Edwin C. |last2=Zhang |first2=Guoqi |last3=Housecroft |first3=Catherine E. |last4=Zampese |first4=Jennifer A. |date=2011 |title=Zinc(ii) coordination polymers, metallohexacycles and metallocapsules—do we understand self-assembly in metallosupramolecular chemistry: algorithms or serendipity? |url=http://dx.doi.org/10.1039/c1ce05884c |journal=CrystEngComm |volume=13 |issue=22 |pages=6864 |doi=10.1039/c1ce05884c |issn=1466-8033|url-access=subscription }}</ref><ref>{{Cite journal |last1=Westcott |first1=Aleema |last2=Fisher |first2=Julie |last3=Harding |first3=Lindsay P. |last4=Rizkallah |first4=Pierre |last5=Hardie |first5=Michaele J. |date=2008-02-16 |title=Self-Assembly of a 3-D Triply Interlocked Chiral [2]Catenane |url=http://dx.doi.org/10.1021/ja8002149 |journal=Journal of the American Chemical Society |volume=130 |issue=10 |pages=2950–2951 |doi=10.1021/ja8002149 |issn=0002-7863 |pmid=18278922|bibcode=2008JAChS.130.2950W |url-access=subscription }}</ref><ref>{{Cite journal |last1=Kuang |first1=Xiaofei |last2=Wu |first2=Xiaoyuan |last3=Yu |first3=Rongmin |last4=Donahue |first4=James P. |last5=Huang |first5=Jinshun |last6=Lu |first6=Can-Zhong |date=2010-04-11 |title=Assembly of a metal–organic framework by sextuple intercatenation of discrete adamantane-like cages |url=http://dx.doi.org/10.1038/nchem.618 |journal=Nature Chemistry |volume=2 |issue=6 |pages=461–465 |bibcode=2010NatCh...2..461K |doi=10.1038/nchem.618 |issn=1755-4330 |pmid=20489714|url-access=subscription }}</ref><ref>{{Cite journal |last1=Heine |first1=Johanna |last2=Schmedt auf der Günne |first2=Jörn |last3=Dehnen |first3=Stefanie |date=2011-07-06 |title=Formation of a Strandlike Polycatenane of Icosahedral Cages for Reversible One-Dimensional Encapsulation of Guests |url=https://pubs.acs.org/doi/10.1021/ja2030273 |journal=Journal of the American Chemical Society |language=en |volume=133 |issue=26 |pages=10018–10021 |doi=10.1021/ja2030273 |issn=0002-7863 |pmid=21657228|bibcode=2011JAChS.13310018H |url-access=subscription }}</ref><ref>{{Cite journal |last1=Torresi |first1=Stefano |last2=Famulari |first2=Antonino |last3=Martí-Rujas |first3=Javier |date=2020-05-20 |title=Kinetically Controlled Fast Crystallization of M 12 L 8 Poly-[ n ]-catenanes Using the 2,4,6-Tris(4-pyridyl)benzene Ligand and ZnCl 2 in an Aromatic Environment |url=https://pubs.acs.org/doi/10.1021/jacs.0c03319 |journal=Journal of the American Chemical Society |language=en |volume=142 |issue=20 |pages=9537–9543 |doi=10.1021/jacs.0c03319 |pmid=32343571 |bibcode=2020JAChS.142.9537T |s2cid=216646315 |issn=0002-7863|url-access=subscription }}</ref><ref>{{Cite journal |last=Marti-Rujas, J.; Famulari, A. |date=2024 |title=Polycatenanes Formed of Self-Assembled Metal Organic Cages |url=https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202407626 |journal=Angewandte Chemie International Edition|volume= 63|issue= 34|pages= e202407626|doi= 10.1002/anie.202407626|pmid= 38837637|url-access=subscription}}</ref> Sometimes the catenated cages structure is more stable with respect to the monomeric cage state, and it can be formed passing through a favored reaction intermediate.<ref>{{Cite journal |last1=Xu |first1=Shijun |last2=Li |first2=Pan |last3=Li |first3=Zi-Ying |last4=Yu |first4=Chunyang |last5=Liu |first5=Xiaoyun |last6=Liu |first6=Zhiqiang |last7=Zhang |first7=Shaodong |date=July 2021 |title=Catenated Cages Mediated by Enthalpic Reaction Intermediates |journal=CCS Chemistry |volume=3 |issue=7 |pages=1838–1850 |doi=10.31635/ccschem.020.202000360 |issn=2096-5745 |s2cid=224904423|doi-access=free }}</ref> The synthesis can follow a statistical or a directed routes, forming more or less product, but there are some cases when post-synthetic modifications can increase the product yields.<ref name="ReferenceA">{{Cite journal |last1=Wu |first1=Yong |last2=Guo |first2=Qing-Hui |last3=Qiu |first3=Yunyan |last4=Weber |first4=Jacob A. |last5=Young |first5=Ryan M. |last6=Bancroft |first6=Laura |last7=Jiao |first7=Yang |last8=Chen |first8=Hongliang |last9=Song |first9=Bo |last10=Liu |first10=Wenqi |last11=Feng |first11=Yuanning |last12=Zhao |first12=Xingang |last13=Li |first13=Xuesong |last14=Zhang |first14=Long |last15=Chen |first15=Xiao-Yang |date=2022-03-22 |title=Syntheses of three-dimensional catenanes under kinetic control |journal=Proceedings of the National Academy of Sciences |language=en |volume=119 |issue=12 |pages=e2118573119 |bibcode=2022PNAS..11918573W |doi=10.1073/pnas.2118573119 |doi-access=free |issn=0027-8424 |pmc=8944772 |pmid=35290119}}</ref><ref>{{Cite journal |last1=Li |first1=Pan |last2=Xu |first2=Shijun |last3=Yu |first3=Chunyang |last4=Li |first4=Zi-Ying |last5=Xu |first5=Jianping |last6=Li |first6=Zi-Mu |last7=Zou |first7=Lingyi |last8=Leng |first8=Xuebing |last9=Gao |first9=Shan |last10=Liu |first10=Zhiqiang |last11=Liu |first11=Xiaoyun |last12=Zhang |first12=Shaodong |date=2020-04-27 |title=De Novo Construction of Catenanes with Dissymmetric Cages by Space-Discriminative Post-Assembly Modification |url=https://onlinelibrary.wiley.com/doi/10.1002/anie.202000442 |journal=Angewandte Chemie International Edition |language=en |volume=59 |issue=18 |pages=7113–7121 |doi=10.1002/anie.202000442 |pmid=32003925 |issn=1433-7851 |s2cid=210982600|url-access=subscription }}</ref> Catenated cages can be applied in a wide range of application due to the high presence of voids.<ref>{{Cite journal |last1=Cheng |first1=Liwei |last2=Liang |first2=Chengyu |last3=Liu |first3=Wei |last4=Wang |first4=Yaxing |last5=Chen |first5=Bin |last6=Zhang |first6=Hailong |last7=Wang |first7=Yanlong |last8=Chai |first8=Zhifang |last9=Wang |first9=Shuao |date=2020-09-03 |title=Three-Dimensional Polycatenation of a Uranium-Based Metal–Organic Cage: Structural Complexity and Radiation Detection |url=http://dx.doi.org/10.1021/jacs.0c08117 |journal=Journal of the American Chemical Society |volume=142 |issue=38 |pages=16218–16222 |doi=10.1021/jacs.0c08117 |issn=0002-7863 |pmid=32881493 |bibcode=2020JAChS.14216218C |s2cid=221496523|url-access=subscription }}</ref><ref>{{Cite journal |last1=Marti-Rujas |first1=Javier |last2=Elli |first2=Stefano |last3=Famulari |first3=Antonino |title=Kinetic trapping of 2,4,6-tris(4-pyridyl)benzene and ZnI2 into M12L8 poly-[n]-catenanes using solution and solid-state processes |journal=Scientific Reports |date=2023 |volume=13 |issue=1 |pages=5605 (2023)|doi=10.1038/s41598-023-32661-x |pmid=37019947 |pmc=10076325 }}</ref><ref>{{Cite journal |last=Marti-Rujas, J. |date=2023 |title=Connecting metal–organic cages (MOCs) for CO2 remediation |journal=Materials Advances |volume=4 |issue=19 |pages=4333–4343|doi=10.1039/D3MA00477E |doi-access=free }}</ref>

== Synthesis and applications ==

=== Synthesis ===
The synthesis of polycatenanes is considered a challenging task with most of the reported examples being in the solution state and very few in the solid state.<ref>{{Cite journal |last=Marti-Rujas, J.; Elli, S.; Sacchetti, A.; Castiglione, F. |date=2022 |title=Mechanochemical synthesis of mechanical bonds in M12L8 poly-[n]-catenanes |url=https://pubs.rsc.org/en/content/articlelanding/2022/dt/d1dt03158a |journal=Dalton Transactions |volume=51 |issue=1 |pages=53–58|doi= 10.1039/D1DT03158A|pmid= 34889335|url-access=subscription }}</ref> The formation of poly-[''2'']-catenanes can be achieved by polymerisation of functionalised [''2'']-catenanes.<ref name=":9">{{Cite journal |last1=Li |first1=Ziyong |last2=Liu |first2=Wenju |last3=Wu |first3=Jishan |last4=Liu |first4=Sheng Hua |last5=Yin |first5=Jun |date=2012-08-17 |title=Synthesis of [2]Catenanes by Template-Directed Clipping Approach |url=https://pubs.acs.org/doi/10.1021/jo3012804 |journal=The Journal of Organic Chemistry |language=en |volume=77 |issue=16 |pages=7129–7135 |doi=10.1021/jo3012804 |issn=0022-3263 |pmid=22839768|url-access=subscription }}</ref> Also the synthesis of [''3'']-catenanes, [''5'']-catenanes, [''6'']-catenanes and [''7'']-catenanes is reported in many articles.<ref>{{Cite journal |last1=Fujita |first1=Makoto |last2=Ogura |first2=Katsuyuki |date=March 1996 |title=Self-assembling [2]catenanes: molecular magic rings |journal=Supramolecular Science |volume=3 |issue=1–3 |pages=37–44 |doi=10.1016/0968-5677(96)00004-1 |issn=0968-5677|doi-access=free }}</ref><ref>{{Cite journal |last1=Amabilino |first1=David B. |last2=Ashton |first2=Peter R. |last3=Balzani |first3=Vincenzo |last4=Boyd |first4=Sue E. |last5=Credi |first5=Alberto |last6=Lee |first6=Ju Young |last7=Menzer |first7=Stephan |last8=Stoddart |first8=J. Fraser |last9=Venturi |first9=Margherita |last10=Williams |first10=David J. |date=1998-04-28 |title=Oligocatenanes Made to Order<sup>1</sup> |url=http://dx.doi.org/10.1021/ja9720873 |journal=Journal of the American Chemical Society |volume=120 |issue=18 |pages=4295–4307 |doi=10.1021/ja9720873 |bibcode=1998JAChS.120.4295A |issn=0002-7863|url-access=subscription }}</ref> The synthesis of poly-[''n'']-catenanes has instead some practical issues.<ref>{{Cite journal |last1=Clarkson |first1=Guy J |last2=Leigh |first2=David A |last3=Smith |first3=Richard A |date=1998-12-01 |title=From catenanes to mechanically-linked polymers |url=https://www.sciencedirect.com/science/article/pii/S1359028698800296 |journal=Current Opinion in Solid State and Materials Science |language=en |volume=3 |issue=6 |pages=579–584 |doi=10.1016/S1359-0286(98)80029-6 |bibcode=1998COSSM...3..579C |issn=1359-0286|url-access=subscription }}</ref><ref>{{Cite journal |last1=Liu |first1=Guancen |last2=Rauscher |first2=Phillip M. |last3=Rawe |first3=Benjamin W. |last4=Tranquilli |first4=Marissa M. |last5=Rowan |first5=Stuart J. |date=2022 |title=Polycatenanes: synthesis, characterization, and physical understanding |url=http://xlink.rsc.org/?DOI=D2CS00256F |journal=Chemical Society Reviews |language=en |volume=51 |issue=12 |pages=4928–4948 |doi=10.1039/D2CS00256F |pmid=35611843 |s2cid=249045606 |issn=0306-0012|url-access=subscription }}</ref> To this purpose, [[Molecular dynamics|molecular dynamic simulation]] is very used as a tool for the design of the optimal synthetic path toward the desired product by predicting the final topology.<ref>{{Cite journal |last1=Lei |first1=Huanqing |last2=Zhang |first2=Jianguo |last3=Wang |first3=Liming |last4=Zhang |first4=Guojie |date=2021-01-06 |title=Dimensional and shape properties of a single linear polycatenane: Effect of catenation topology |url=https://www.sciencedirect.com/science/article/pii/S003238612030985X |journal=Polymer |language=en |volume=212 |pages=123160 |doi=10.1016/j.polymer.2020.123160 |issn=0032-3861 |s2cid=228825803|url-access=subscription }}</ref><ref name=":6" />

There are two main synthetic routes: the statistical approach and the template-directed approach.<ref name=":3">{{Cite journal |last1=Raymo |first1=Françisco M. |last2=Stoddart |first2=J. Fraser |date=1999-06-11 |title=Interlocked Macromolecules |url=http://dx.doi.org/10.1021/cr970081q |journal=Chemical Reviews |volume=99 |issue=7 |pages=1643–1664 |doi=10.1021/cr970081q |issn=0009-2665 |pmid=11849006|url-access=subscription }}</ref>

The statistical approach is based on a stochastic methodology.<ref name=":7">{{Cite journal |last1=Agam |first1=Giora |last2=Zilkha |first2=Albert |date=August 1976 |title=Synthesis of a catenane by a statistical double-stage method |url=https://pubs.acs.org/doi/abs/10.1021/ja00433a027 |journal=Journal of the American Chemical Society |language=en |volume=98 |issue=17 |pages=5214–5216 |doi=10.1021/ja00433a027 |bibcode=1976JAChS..98.5214A |issn=0002-7863|url-access=subscription }}</ref><ref name=":8">{{Cite journal |last=Harrison |first=I. T. |date=1972 |title=The effect of ring size on threading reactions of macrocycles |url=http://xlink.rsc.org/?DOI=c39720000231 |journal=Journal of the Chemical Society, Chemical Communications |language=en |issue=4 |pages=231–232 |doi=10.1039/c39720000231 |issn=0022-4936|url-access=subscription }}</ref> When the reactants are together, there is a probability that they will fit together first and then close on top of each other in a process of cyclisation. The catenation of two rings into a catenane is already complex, thus, as expected, the interlocking of multiple cycles into a polycatenane is statistically improbable. Being an unfavored entropically process the product is obtained in very small amounts. Also, the cyclisation process requires high dilutions, but the elongation of the chain is favored at high concentrations, making the synthesis even more difficult.<ref name=":7" /><ref name=":8" />
[[File:Template-Directed Clipping Approach for the Synthesis of Catenanes.gif|thumb|upright=1.5|Example of template-directed clipping approach for the synthesis of catenanes.<ref name=":9"/>]]
The template-directed approach is based on the host-guest interactions that can direct the cyclisation of pre-organised linear unit upon the existing macrocycle.<ref name=":3" /><ref name=":9"/> These interactions can be hydrogen bonds, π-π interactions, hydrophobic interactions or metal ions coordinations. In this way the synthesis can be enthalpy-driven, obtaining quantitative results.<ref name=":3" /><ref name=":9" />

The yield and selectivity are restrained by the kinetic or thermodynamic control of the reaction.<ref>{{Cite journal |last1=Dichtel |first1=William R. |last2=Miljanić |first2=Ognjen Š. |last3=Zhang |first3=Wenyu |last4=Spruell |first4=Jason M. |last5=Patel |first5=Kaushik |last6=Aprahamian |first6=Ivan |last7=Heath |first7=James R. |last8=Stoddart |first8=J. Fraser |date=2008-12-16 |title=Kinetic and Thermodynamic Approaches for the Efficient Formation of Mechanical Bonds |url=https://pubs.acs.org/doi/10.1021/ar800067h |journal=Accounts of Chemical Research |language=en |volume=41 |issue=12 |pages=1750–1761 |doi=10.1021/ar800067h |issn=0001-4842 |pmid=18837521}}</ref>

Generally the kinetic control induces the formation of a product after short reaction times because it is favoued by irreversible reactions (or equilibrium reaction moved very much toward the formation of the products).<ref name="ReferenceA"/> The thermodynamic product is obtained for longer reaction times for reversible processes.<ref>{{Cite journal |last1=Olson |first1=Mark A. |last2=Coskun |first2=Ali |last3=Fang |first3=Lei |last4=Basuray |first4=Ashish N. |last5=Stoddart |first5=J. Fraser |date=2010-04-19 |title=Polycatenation under Thermodynamic Control |url=http://dx.doi.org/10.1002/ange.201000421 |journal=Angewandte Chemie |volume=122 |issue=18 |pages=3219–3224 |bibcode=2010AngCh.122.3219O |doi=10.1002/ange.201000421 |issn=0044-8249|url-access=subscription }}</ref> In this case the units have the time to rearrange themselves toward the most stable state, in a sort of error-checking process. This is obtained by breaking covalent and coordination bonds and forming the most stable ones.<ref>{{Cite journal |last1=Sartori |first1=Pablo |last2=Pigolotti |first2=Simone |date=2015-12-10 |title=Thermodynamics of Error Correction |url=https://link.aps.org/doi/10.1103/PhysRevX.5.041039 |journal=Physical Review X |volume=5 |issue=4 |pages=041039 |arxiv=1504.06407 |bibcode=2015PhRvX...5d1039S |doi=10.1103/PhysRevX.5.041039 |s2cid=14086928}}</ref>

=== Applications ===
Given that polycatenanes are a relatively recent field of study, the properties of these materials are not yet fully explored and understood.<ref>{{Cite journal |last1=Hart |first1=Laura F. |last2=Hertzog |first2=Jerald E. |last3=Rauscher |first3=Phillip M. |last4=Rawe |first4=Benjamin W. |last5=Tranquilli |first5=Marissa M. |last6=Rowan |first6=Stuart J. |date=2021-02-12 |title=Material properties and applications of mechanically interlocked polymers |url=http://dx.doi.org/10.1038/s41578-021-00278-z |journal=Nature Reviews Materials |volume=6 |issue=6 |pages=508–530 |doi=10.1038/s41578-021-00278-z |bibcode=2021NatRM...6..508H |osti=1812714 |s2cid=231905660 |issn=2058-8437}}</ref> The type of bonds that characterize the whole structure (covalent, non-covalent or mechanical bonds), the degree of mobility of the chain, the interactions between different chains and the fraction of voids of the catenanes are all factors that contribute to the final properties. As they can be strictly related to the family of [[Metal–organic framework|metal-organic frameworks]], the catenanes share all the potential applications of this class of compounds. Among these, there are applications in biomedicine, catalysis, as conducting bridges or in electronic devices, sensing or in recent fields like molecular machines.<ref>{{Cite journal |last1=Riebe |first1=Jan |last2=Niemeyer |first2=Jochen |date=2021-10-07 |title=Mechanically Interlocked Molecules for Biomedical Applications |journal=European Journal of Organic Chemistry |language=en |volume=2021 |issue=37 |pages=5106–5116 |doi=10.1002/ejoc.202100749 |issn=1434-193X |s2cid=238738743|doi-access=free }}</ref><ref>{{Cite journal |last1=van Dongen |first1=Stijn F. M. |last2=Cantekin |first2=Seda |last3=Elemans |first3=Johannes A. A. W. |last4=Rowan |first4=Alan E. |last5=Nolte |first5=Roeland J. M. |date=2014 |title=Functional interlocked systems |url=http://dx.doi.org/10.1039/c3cs60178a |journal=Chem. Soc. Rev. |volume=43 |issue=1 |pages=99–122 |doi=10.1039/c3cs60178a |issn=0306-0012 |pmid=24071686 |s2cid=11174780|hdl=2066/128395 |hdl-access=free }}</ref><ref>{{Cite journal |last1=Langton |first1=Matthew J. |last2=Beer |first2=Paul D. |date=2014-04-07 |title=Rotaxane and Catenane Host Structures for Sensing Charged Guest Species |url=http://dx.doi.org/10.1021/ar500012a |journal=Accounts of Chemical Research |volume=47 |issue=7 |pages=1935–1949 |doi=10.1021/ar500012a |issn=0001-4842 |pmid=24708030|url-access=subscription }}</ref><ref>{{Cite journal |last1=Evans |first1=Nicholas H. |last2=Beer |first2=Paul D. |date=2014 |title=Progress in the synthesis and exploitation of catenanes since the Millennium |url=http://xlink.rsc.org/?DOI=c4cs00029c |journal=Chemical Society Reviews |language=en |volume=43 |issue=13 |pages=4658–4683 |doi=10.1039/c4cs00029c |issn=0306-0012 |pmid=24676138|url-access=subscription }}</ref><ref>{{Cite journal |last1=Chen |first1=Hongliang |last2=Fraser Stoddart |first2=J. |date=September 2021 |title=From molecular to supramolecular electronics |url=https://www.nature.com/articles/s41578-021-00302-2 |journal=Nature Reviews Materials |language=en |volume=6 |issue=9 |pages=804–828 |bibcode=2021NatRM...6..804C |doi=10.1038/s41578-021-00302-2 |issn=2058-8437 |s2cid=232766622|url-access=subscription }}</ref><ref>{{Cite journal |last1=Caballero |first1=Antonio |last2=Zapata |first2=Fabiola |last3=Beer |first3=Paul D. |date=September 2013 |title=Interlocked host molecules for anion recognition and sensing |url=http://dx.doi.org/10.1016/j.ccr.2013.01.016 |journal=Coordination Chemistry Reviews |volume=257 |issue=17–18 |pages=2434–2455 |doi=10.1016/j.ccr.2013.01.016 |issn=0010-8545|url-access=subscription }}</ref><ref>{{Cite journal |last=Aprahamian |first=Ivan |date=2020-03-03 |title=The Future of Molecular Machines |url=http://dx.doi.org/10.1021/acscentsci.0c00064 |journal=ACS Central Science |volume=6 |issue=3 |pages=347–358 |doi=10.1021/acscentsci.0c00064 |issn=2374-7943 |pmid=32232135 |pmc=7099591 |s2cid=214703064}}</ref>

== See also ==

* [[Mechanically interlocked molecular architectures]]
* [[Catenane]]
* [[Macrocycle]]
* [[Coordination cage]]
* [[Macromolecular cages]]
* [[Macromolecule]]
* [[Metal-organic compound]]
* [[Metal–organic framework]]

== References ==
{{reflist}}

== Further reading ==

* {{Cite journal |last=Stoddart |first=J. Fraser |date=2017-09-04 |title=Mechanically Interlocked Molecules (MIMs)-Molecular Shuttles, Switches, and Machines (Nobel Lecture) |journal=Angewandte Chemie International Edition |language=en |volume=56 |issue=37 |pages=11094–11125 |doi=10.1002/anie.201703216|pmid=28815900 |doi-access=free }}
* {{Cite book |url=http://dx.doi.org/10.1002/9780470606858 |title=Metal-Organic Frameworks |date=June 2010 |publisher=Wiley |doi=10.1002/9780470606858 |isbn=978-0-470-19556-7 |editor-last=MacGillivray |editor-first=Leonard R.}}
* {{Cite book |last1=Davis |first1=Frank |title=Macrocycles: construction, chemistry, and nanotechnology applications |last2=Higson |first2=Séamus |date=2011 |publisher=Wiley |isbn=978-1-119-98993-6 |location=Chichester}}
* {{Cite journal |last1=Au-Yeung |first1=Ho Yu |last2=Deng |first2=Yulin |date=2022 |title=Distinctive features and challenges in catenane chemistry |journal=Chemical Science |language=en |volume=13 |issue=12 |pages=3315–3334 |doi=10.1039/D1SC05391D |issn=2041-6520 |pmc=8943846 |pmid=35432874}}
* {{Citation |last1=Ricketts |first1=H. G. |title=A Simple Approach to Modelling Supramolecular Complexes and Mechanically-Interlocked Molecules |date=1994 |url=http://dx.doi.org/10.1007/978-94-011-1058-7_24 |work=Computational Approaches in Supramolecular Chemistry |pages=377–390 |access-date=2023-07-06 |place=Dordrecht |publisher=Springer Netherlands |isbn=978-94-010-4460-8 |last2=Stoddart |first2=J. F. |last3=Hann |first3=M. M.|doi=10.1007/978-94-011-1058-7_24 |url-access=subscription }}
* {{Cite journal |last1=Gibson |first1=Harry W. |last2=Bheda |first2=Mukesh C. |last3=Engen |first3=Paul T. |date=January 1994 |title=Rotaxanes, catenanes, polyrotaxanes, polycatenanes and related materials |url=http://dx.doi.org/10.1016/0079-6700(94)90034-5 |journal=Progress in Polymer Science |volume=19 |issue=5 |pages=843–945 |doi=10.1016/0079-6700(94)90034-5 |issn=0079-6700|url-access=subscription }}
* {{Cite journal |last1=Amabilino |first1=D. B. |last2=Stoddart |first2=J. Fraser |date=January 1993 |title=Self-assembly and macromolecular design |journal=Pure and Applied Chemistry |volume=65 |issue=11 |pages=2351–2359 |doi=10.1351/pac199365112351 |s2cid=62797149 |issn=1365-3075|doi-access=free }}
* {{Cite journal |last1=Tubiana |first1=L. |last2=Ferrari |first2=F. |last3=Orlandini |first3=E. |date=November 2022 |title=Circular Polycatenanes: Supramolecular Structures with Topologically Tunable Properties |url=http://dx.doi.org/10.1103/physrevlett.129.227801 |journal=Physical Review Letters |volume=129 |issue=22 |page=227801 |doi=10.1103/physrevlett.129.227801 |pmid=36493458 |arxiv=2112.08973 |bibcode=2022PhRvL.129v7801T |s2cid=253875441 |issn=0031-9007}}
* {{Cite journal |last1=Jiang |first1=Long |last2=Ju |first2=Ping |last3=Meng |first3=Xian-Rui |last4=Kuang |first4=Xiao-Jun |last5=Lu |first5=Tong-Bu |date=September 2012 |title=Constructions of two polycatenanes and one polypseudo-rotaxane by discrete tetrahedral cages and stool-like building units |url=http://dx.doi.org/10.1038/srep00668 |journal=Scientific Reports |volume=2 |issue=1 |page=668 |doi=10.1038/srep00668 |pmid=22993693 |pmc=3444800 |bibcode=2012NatSR...2E.668J |issn=2045-2322}}
* {{Cite journal |last1=Muscat |first1=Dirk |last2=Witte |first2=Andreas |last3=Köhler |first3=Werner |last4=Müllen |first4=Klaus |last5=Geerts |first5=Yves |date=March 1997 |title=Synthesis of a novel poly[2]-catenane containing rigid catenanes |url=http://dx.doi.org/10.1002/marc.1997.030180304 |journal=Macromolecular Rapid Communications |volume=18 |issue=3 |pages=233–241 |doi=10.1002/marc.1997.030180304 |issn=1022-1336|url-access=subscription }}
* {{Cite journal |last1=Colley |first1=Nathan D. |last2=Nosiglia |first2=Mark A. |last3=Tran |first3=Sheila L. |last4=Harlan |first4=Gray H. |last5=Chang |first5=Christy |last6=Li |first6=Ruihan |last7=Delawder |first7=Abigail O. |last8=Zhang |first8=Yipei |last9=Barnes |first9=Jonathan C. |date=November 2022 |title=Topologically Controlled Syntheses of Unimolecular Oligo[''n'']catenanes |url=http://dx.doi.org/10.1021/acscentsci.2c00697 |journal=ACS Central Science |volume=8 |issue=12 |pages=1672–1682 |doi=10.1021/acscentsci.2c00697 |pmid=36589894 |pmc=9801505 |issn=2374-7943}}
* {{Cite journal |last1=Bria |first1=Marc |last2=Bigot |first2=Julien |last3=Cooke |first3=Graeme |last4=Lyskawa |first4=Joël |last5=Rabani |first5=Gouher |last6=Rotello |first6=Vincent M. |last7=Woisel |first7=Patrice |date=January 2009 |title=Synthesis of a polypseudorotaxane, polyrotaxane, and polycatenane using 'click' chemistry |url=http://dx.doi.org/10.1016/j.tet.2008.10.005 |journal=Tetrahedron |volume=65 |issue=1 |pages=400–407 |doi=10.1016/j.tet.2008.10.005 |issn=0040-4020|url-access=subscription }}
* {{Cite journal |last1=Schill |first1=G. |last2=Lüttringhaus |first2=A. |date=August 1964 |title=The Preparation of Catena Compounds by Directed Synthesis |url=http://dx.doi.org/10.1002/anie.196405461 |journal=Angewandte Chemie International Edition in English |volume=3 |issue=8 |pages=546–547 |doi=10.1002/anie.196405461 |issn=0570-0833|url-access=subscription }}
* {{Cite journal |last1=Datta |first1=Sougata |last2=Kato |first2=Yasuki |last3=Higashiharaguchi |first3=Seiya |last4=Aratsu |first4=Keisuke |last5=Isobe |first5=Atsushi |last6=Saito |first6=Takuho |last7=Prabhu |first7=Deepak D. |last8=Kitamoto |first8=Yuichi |last9=Hollamby |first9=Martin J. |last10=Smith |first10=Andrew J. |last11=Dalgliesh |first11=Robert |last12=Mahmoudi |first12=Najet |last13=Pesce |first13=Luca |last14=Perego |first14=Claudio |last15=Pavan |first15=Giovanni M. |date=July 2020 |title=Self-assembled poly-catenanes from supramolecular toroidal building blocks |url=https://www.nature.com/articles/s41586-020-2445-z |journal=Nature |language=en |volume=583 |issue=7816 |pages=400–405 |doi=10.1038/s41586-020-2445-z |pmid=32669695 |bibcode=2020Natur.583..400D |s2cid=220543584 |issn=1476-4687|url-access=subscription }}
* {{Cite journal |last1=Niemeyer |first1=Jochen |last2=Pairault |first2=Noel |date=2018-02-26 |title=Chiral Mechanically Interlocked Molecules – Applications of Rotaxanes, Catenanes and Molecular Knots in Stereoselective Chemosensing and Catalysis |url=http://dx.doi.org/10.1055/s-0036-1591934 |journal=Synlett |volume=29 |issue=6 |pages=689–698 |doi=10.1055/s-0036-1591934 |s2cid=102819256 |issn=0936-5214|url-access=subscription }}

== External links ==

* {{Cite web |title=Stoddart Group |url=https://stoddart.northwestern.edu/ |access-date=2023-07-06}}
* {{Cite web |title=Interlocked molecules articles from across Nature Portfolio |url=https://www.nature.com/subjects/interlocked-molecules#:~:text=Interlocked%20molecules%20are%20molecular%20architectures,molecules%20include%20catenanes%20and%20rotaxanes. |access-date=2023-07-06}}

[[Category:Polymers]]
[[Category:Supramolecular chemistry]]
[[Category:Molecular topology]]
[[Category:Macrocycles]]