Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes

Strauss, Michael J.; Asheghali, Darya; Evans, Austin M.; Li, Rebecca L.; Chavez, Anton D.; Sun, Chao; Becker, Matthew L.; Dichtel, William R.

doi:10.1002/anie.201907668

Title: Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes

Abstract

Abstract Nanotubes assembled from macrocyclic precursors offer a unique combination of low dimensionality, structural rigidity, and distinct interior and exterior microenvironments. Usually the weak stacking energies of macrocycles limit the length and mechanical strength of the resultant nanotubes. Imine‐linked macrocycles were recently found to assemble into high‐aspect ratio (>10 ³ ), lyotropic nanotubes in the presence of excess acid. Yet these harsh conditions are incompatible with many functional groups and processing methods, and lower acid loadings instead catalyze macrocycle degradation. Here we report pyridine‐2,6‐diimine‐linked macrocycles that assemble into high‐aspect ratio nanotubes in the presence of less than 1 equiv of CF ₃ CO ₂ H per macrocycle. Analysis by gel permeation chromatography and fluorescence spectroscopy revealed a cooperative self‐assembly mechanism. The low acid concentrations needed to induce assembly enabled nanofibers to be obtained by touch‐spinning, which exhibit higher Young's moduli (1.33 GPa) than many synthetic polymers and biological filaments. These findings represent a breakthrough in the design of inverse chromonic liquid crystals, as assembly under such mild conditions will enable the design of structurally diverse and mechanically robust nanotubes from synthetically accessible macrocycles.

Authors:

^[1];

^[2];

^[1];

^[1]; Chavez, Anton D. ^[3]; Sun, Chao ^[3];

^[2];

^[1]

Department of Chemistry Northwestern University 2145 Sheridan Road Evanston IL 60208 USA
Department of Polymer Science The University of Akron Akron OH 44325 USA
Department of Chemistry Northwestern University 2145 Sheridan Road Evanston IL 60208 USA, Department of Chemistry and Chemical Biology, Baker Laboratory Cornell University Ithaca NY 14853 USA

Publication Date:: Fri Sep 13 00:00:00 EDT 2019

Sponsoring Org.:: USDOE

OSTI Identifier:: 1562124

Grant/Contract Number:: DGE-1324585

Resource Type:: Publisher's Accepted Manuscript

Journal Name:: Angewandte Chemie (International Edition)

Additional Journal Information:: Journal Name: Angewandte Chemie (International Edition) Journal Volume: 58 Journal Issue: 41; Journal ID: ISSN 1433-7851

Publisher:: Wiley Blackwell (John Wiley & Sons)

Country of Publication:: Germany

Language:: English

Citation Formats


                    Strauss, Michael J., Asheghali, Darya, Evans, Austin M., Li, Rebecca L., Chavez, Anton D., Sun, Chao, Becker, Matthew L., and Dichtel, William R. Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes.  Germany: N. p., 2019. 
Web.  doi:10.1002/anie.201907668.

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                    Strauss, Michael J., Asheghali, Darya, Evans, Austin M., Li, Rebecca L., Chavez, Anton D., Sun, Chao, Becker, Matthew L., & Dichtel, William R. Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes.  Germany.  https://doi.org/10.1002/anie.201907668

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                    Strauss, Michael J., Asheghali, Darya, Evans, Austin M., Li, Rebecca L., Chavez, Anton D., Sun, Chao, Becker, Matthew L., and Dichtel, William R. Fri .  
"Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes".  Germany.  https://doi.org/10.1002/anie.201907668.

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@article{osti_1562124,

  title        = {Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes},

  author       = {Strauss, Michael J. and Asheghali, Darya and Evans, Austin M. and Li, Rebecca L. and Chavez, Anton D. and Sun, Chao and Becker, Matthew L. and Dichtel, William R.},

  abstractNote = {Abstract Nanotubes assembled from macrocyclic precursors offer a unique combination of low dimensionality, structural rigidity, and distinct interior and exterior microenvironments. Usually the weak stacking energies of macrocycles limit the length and mechanical strength of the resultant nanotubes. Imine‐linked macrocycles were recently found to assemble into high‐aspect ratio (>10 3 ), lyotropic nanotubes in the presence of excess acid. Yet these harsh conditions are incompatible with many functional groups and processing methods, and lower acid loadings instead catalyze macrocycle degradation. Here we report pyridine‐2,6‐diimine‐linked macrocycles that assemble into high‐aspect ratio nanotubes in the presence of less than 1 equiv of CF 3 CO 2 H per macrocycle. Analysis by gel permeation chromatography and fluorescence spectroscopy revealed a cooperative self‐assembly mechanism. The low acid concentrations needed to induce assembly enabled nanofibers to be obtained by touch‐spinning, which exhibit higher Young's moduli (1.33 GPa) than many synthetic polymers and biological filaments. These findings represent a breakthrough in the design of inverse chromonic liquid crystals, as assembly under such mild conditions will enable the design of structurally diverse and mechanically robust nanotubes from synthetically accessible macrocycles.},

  doi          = {10.1002/anie.201907668},

  journal      = {Angewandte Chemie (International Edition)},

  number       = 41,

  volume       = 58,

  place        = {Germany},

  year         = {Fri Sep 13 00:00:00 EDT 2019},

  month        = {Fri Sep 13 00:00:00 EDT 2019}

}

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Title: Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes

Abstract

Citation Formats

Unusually Large Young’s Moduli of Amino Acid Molecular Crystals journal, September 2015

Helical microtubules of graphitic carbon journal, November 1991

Touch- and Brush-Spinning of Nanofibers journal, September 2015

Equilibration of Imine-Linked Polymers to Hexagonal Macrocycles Driven by Self-Assembly journal, February 2018

Topology and dynamics of active nematic vesicles journal, September 2014

Phenylalanine-Based Poly(ester urea): Synthesis, Characterization, and in vitro Degradation journal, December 2013

Organische Nanoröhren durch Selbstorganisation journal, March 2001

Biological Templated Synthesis of Water-Soluble Conductive Polymeric Nanowires journal, December 2007

Self-Assembling Organic Nanotubes journal, March 2001

Functional Supramolecular Polymers journal, February 2012

Supramolecular Liquid Crystals Based on Cyclo[8]pyrrole journal, February 2007

High aspect ratio nanotubes assembled from macrocyclic iminium salts journal, August 2018

Self-Assembled Organic Nanostructures with Metallic-Like Stiffness journal, September 2010

Columnar Liquid-Crystalline Metallomacrocycles journal, February 2015

Measurement of Elastic Modulus of Collagen Type I Single Fiber journal, January 2016

Unusually Large Young’s Moduli of Amino Acid Molecular Crystals journal, September 2015

Supramolecular Liquid Crystals Based on Cyclo[8]pyrrole journal, February 2007

Self-assembly on optical fibers: a powerful nanofabrication tool for next generation “lab-on-fiber” optrodes journal, January 2018

Compliance of thin filaments in skinned fibers of rabbit skeletal muscle journal, September 1995

Manipulation of Discrete Nanostructures by Selective Modulation of Noncovalent Forces journal, April 2014

Nematic Liquid Crystallinity of Multiwall Carbon Nanotubes journal, November 2003

Virus-Enabled Silicon Anode for Lithium-Ion Batteries journal, August 2010

Self-Assembling Peptide Nanotubes journal, January 1996

Columnarly Assembled Liquid-Crystalline Peptidic Macrocycles Unidirectionally Orientable over a Large Area by an Electric Field journal, September 2011

Organic and Organometallic Nanofibers Formed by Supramolecular Assembly of Diamond-Shaped Macrocyclic Ligands and Pd II Complexes journal, March 2013

Self-Assembled Organic Nanostructures with Metallic-Like Stiffness journal, September 2010

Nanoarchitectures. 6. Liquid Crystals Based on Shape-Persistent Macrocyclic Mesogens. journal, March 1994

Shape-Persistent Macrocycles with Intraannular Polar Groups: Synthesis, Liquid Crystallinity, and 2D Organization journal, January 2004

Unusually Large Young’s Moduli of Amino Acid Molecular Crystals
journal, September 2015

Helical microtubules of graphitic carbon
journal, November 1991

Touch- and Brush-Spinning of Nanofibers
journal, September 2015

Equilibration of Imine-Linked Polymers to Hexagonal Macrocycles Driven by Self-Assembly
journal, February 2018

Topology and dynamics of active nematic vesicles
journal, September 2014

Phenylalanine-Based Poly(ester urea): Synthesis, Characterization, and in vitro Degradation
journal, December 2013

Organische Nanoröhren durch Selbstorganisation
journal, March 2001

Biological Templated Synthesis of Water-Soluble Conductive Polymeric Nanowires
journal, December 2007

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Functional Supramolecular Polymers
journal, February 2012

Supramolecular Liquid Crystals Based on Cyclo[8]pyrrole
journal, February 2007

High aspect ratio nanotubes assembled from macrocyclic iminium salts
journal, August 2018

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journal, September 2010

Columnar Liquid-Crystalline Metallomacrocycles
journal, February 2015

Measurement of Elastic Modulus of Collagen Type I Single Fiber
journal, January 2016

Unusually Large Young’s Moduli of Amino Acid Molecular Crystals
journal, September 2015

Supramolecular Liquid Crystals Based on Cyclo[8]pyrrole
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Organic and Organometallic Nanofibers Formed by Supramolecular Assembly of Diamond-Shaped Macrocyclic Ligands and Pd ^II Complexes
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