Thi Minh Thi Tran

All Publications

• Synthesis and Thermo-Selective Recycling of Diels-Alder Cyclopentadiene Thermoplastics. Journal of the American Chemical Society Tran, T. M., Read de Alaniz, J. 2024

  Abstract

  Catalyst-free and reversible step-growth Diels-Alder (DA) polymerization has a wide range of applications in polymer synthesis and is a promising method for fabricating recyclable thermoplastics. The effectiveness of polymerization and depolymerization relies on the chemical building blocks, often utilizing furan as the diene and maleimide as the dienophile. Compared to the traditional diene-dienophile or two-component approach that requires precise stoichiometry, cyclopentadiene (Cp) can serve dual roles via self-dimerization. This internally balanced platform offers a route to access high-molecular-weight polymers and a dynamic handle for polymer recycling, which has yet to be explored. Herein, through a reactivity investigation of different telechelic Cp derivatives, the uncontrolled cross-linking of Cp was addressed, revealing the first successful DA homopolymerization. To demonstrate the generality of our methodology, we synthesized and characterized six Cp homopolymers with backbones derived from common thermoplastics, such as poly(dimethylsiloxane), hydrogenated polybutadiene, and ethylene phthalate. Among these materials, the hydrogenated polybutadiene-Cp analog can be thermally depolymerized (Mn = 68 to 23 kDa) and repolymerized to the parent polymer (Mn = 68 kDa) under solvent- and catalyst-free conditions. This process was repeated over three cycles without intermediate purification, confirming the efficient thermo-selective recyclability. The varied degradable properties of the other four Cp-incorporated thermoplastics were also examined. Overall, this work provides a general methodology for accessing a new class of reversible homopolymers, potentially expanding the design and construction of sustainable thermoplastics.

  View details for DOI 10.1021/jacs.4c05952

  View details for PubMedID 39041456

• Interfacial doping of semiconducting polymers with phenothiazine-based polymeric ionic liquids JOURNAL OF MATERIALS CHEMISTRY C Oh, S., Nguyen, P. H., Tran, T. M., Destefano, A. J., Tagami, K., Yuan, D., Nikolaev, A., Condarcure, M., Han, S., de Alaniz, J., Chabinyc, M. L. 2023; 11 (44): 15435-15442

  View details for DOI 10.1039/d3tc03176d

  View details for Web of Science ID 001092144500001

• Controlled Synthesis of a Homopolymer Network Using a Well-Defined Single-Component Diels-Alder Cyclopentadiene Monomer JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Tran, T. M., de Alaniz, J. 2023; 145 (6): 3462-3469

  Abstract

  Cyclopentadiene is known for its high reactivity and propensity to dimerize, making monomer synthesis and polymerization notoriously challenging. In fact, despite its long history and compelling chemistry, only two reports have appeared in the literature since the first attempt to homopolymerize cyclopentadiene by Staudinger in 1926. Herein, we present a strategy not only to synthesize, isolate, and homopolymerize a well-defined tetracyclopentadiene monomer but also to de-cross-link the network homopolymer. Mechanical properties are also investigated, including creep-recovery, shape memory, and tensile behaviors. Interestingly, the tensile test reflects a tough and elastic material, in contrast to prior Cp-based homopolymer networks. This work provides a versatile platform to access and study new cyclopentadiene-based and better-defined homopolymer networks with potential applications ranging from shape memory polymers to degradable thermosets.

  View details for DOI 10.1021/jacs.2c11416

  View details for Web of Science ID 000927039200001

  View details for PubMedID 36722948

• Redox-Active Polymeric Ionic Liquids with Pendant N-Substituted Phenothiazine ACS APPLIED MATERIALS & INTERFACES Oh, S., Nikolaev, A., Tagami, K., Tran, T., Lee, D., Mukherjee, S., Segalman, R. A., Han, S., de Alaniz, J., Chabinyc, M. L. 2021; 13 (4): 5319-5326

  Abstract

  Polymers that are elastic while supporting charge transport are desirable for flexible and soft electronics. Many polymers with bulky and conjugated redox-active pendant units have high glass transition temperatures (Tg) in their neutral form that will not lead to elasticity at room temperature. Their behavior in charged form in the solid state without an electrolyte has not been extensively studied. Here, the design strategy of polymeric ionic liquid where two weakly interacting ionic groups are used to maintain a low Tg is shown to lead to flexible redox active polymers. The use of a flexible ethylene backbone and redox-active phenothiazine (PTZ)-based pendant group resulted in polymers with relatively low Tg that are electrically conductive. PTZ that was N-substituted with 2-(2-ethoxyethoxy)ethoxy)ethyl was found to promote solubility of the polymer and lower the Tg of the neutral polymer by ∼150 °C relative to that of the Tg of a variant without the N-substituent. Doping with trifluoromethanesulfonimide leads to an electrically conductive polymer without significantly increasing the Tg. Physical characterization by UV-vis-NIR spectroscopy, electron spin resonance spectroscopy, and impedance spectroscopy verified that the molecular design leads to an efficient charge hopping between the PTZ groups.

  View details for DOI 10.1021/acsami.0c20462

  View details for Web of Science ID 000618153100052

  View details for PubMedID 33480673

• Synthesis of (-)-Melodinine K: A Case Study of Efficiency in Natural Product Synthesis JOURNAL OF NATURAL PRODUCTS Walia, M., Teijaro, C. N., Gardner, A., Thi Tran, Kang, J., Zhao, S., O'Connor, S. E., Courdavault, V., Andrade, R. B. 2020; 83 (8): 2425-2433

  Abstract

  Efficiency is a key organizing principle in modern natural product synthesis. Practical criteria include time, cost, and effort expended to synthesize the target, which tracks with step-count and scale. The execution of a natural product synthesis, that is, the sum and identity of each reaction employed therein, falls along a continuum of chemical (abiotic) synthesis on one extreme, followed by the hybrid chemoenzymatic approach, and ultimately biological (biosynthesis) on the other, acknowledging the first synthesis belongs to Nature. Starting materials also span a continuum of structural complexity approaching the target with constituent elements on one extreme, followed by petroleum-derived and "chiral pool" building blocks, and complex natural products (i.e., semisynthesis) on the other. Herein, we detail our approach toward realizing the first synthesis of (-)-melodinine K, a complex bis-indole alkaloid. The total syntheses of monomers (-)-tabersonine and (-)-16-methoxytabersonine employing our domino Michael/Mannich annulation is described. Isolation of (-)-tabersonine from Voacanga africana and strategic biotransformation with tabersonine 16-hydroxylase for site-specific C-H oxidation enabled a scalable route. The Polonovski-Potier reaction was employed in biomimetic fragment coupling. Subsequent manipulations delivered the target. We conclude with a discussion of efficiency in natural products synthesis and how chemical and biological technologies define the synthetic frontier.

  View details for DOI 10.1021/acs.jnatprod.0c00310

  View details for Web of Science ID 000566765000013

  View details for PubMedID 32786883

• Effect of Intercalated Metals on the Electrocatalytic Activity of 1T-MoS₂ for the Hydrogen Evolution Reaction ACS ENERGY LETTERS Attanayake, N. H., Thenuwara, A. C., Patra, A., Aulin, Y. V., Tran, T. M., Chakraborty, H., Borguet, E., Klein, M. L., Perdew, J. P., Strongin, D. R. 2018; 3 (1): 7-13

  View details for DOI 10.1021/acsenergylett.7b00865

  View details for Web of Science ID 000422814500002