Multicomponent polymerization of sulfur, chloroform and diamine toward polythiourea

The efficient utilization of elemental sulfur(S8) for developing high value-added chemicals is a global concern considering its abundant sources and yearly accelerating environmental issues. However, it has been a long-standing challenge to directly transform elemental sulfur to sulfur-containing polymer, especially via an environmentally benign manner. Herein, a unique chemo-differentiating multicomponent polymerization(MCP) of elemental sulfur, chloroform, and diamine is reported to construct polythiourea based on amine-involved two sequential reactions including isothiocyanation and nucleophilic addition.This strategy features isocynide-free monomers as starting materials, mild conditions, high molecular weights(up to72,900 g/mol) and desired yields(up to 83%). With the advantages of inactive isocyanation and active nucleophilic addition, the stoichiometric balance of amine and isothiocyanate could be delicately controlled to afford various polythioureas with high molecular weights. The polythioureas have been further utilized in the Cu-based aqueous catalysis and Hg-based ion adsorption.

Metal-free multicomponent polymerization of activated diyne,electrophilic styrene and isocyanide towards highly substituted and functional poly(cyclopentadiene)

The development of a facile and efficient polymerization to prepare cyclopentadiene-containing polymers is of vital importance and highly desired. In this work, a metal-free multicomponent polymerization of activated diyne, electrophilic styrene and isocyanide for the preparation of highly substituted poly(cyclopentadiene) was established. Soluble and thermally stable polymers with high molecular weights are obtained in high yields under mild conditions. By introducing the tetraphenylethene or triphenylamine moiety into polymer backbones, the resultant polymers show unique aggregation-induced emission(AIE)characteristics. Interestingly, AIE polymers can also be generated in situ from non-AIE monomers. Moreover, the prepared polymers can generate photopatterns to function as photoresists and can also serve as visualizing agents to selectively stain the lipid droplets in live cells. This efficient polymerization will open up enormous opportunities for preparing functional cyclopentadiene-containing polymers applicable in diverse areas.

Functional Polyselenoureas for Selective Gold Recovery Prepared from Catalyst-Free Multicomponent Polymerizations of Elemental Selenium

Selenium-containing polymers with fascinating functionalities such as stimuli-responsive property,enzyme mimics,antioxidant activity,promotion of immune-cell activity,anticancer activity,and controlled delivery property,are highly desired,but rarely developed due to their underexplored synthetic methods.Herein,through careful design of monomeric structures and polymerization conditions,we report a series of catalyst-free multicomponent polymerizations(MCPs)of elemental selenium with aliphatic/aromatic diamines and diisocyanides that directly converted selenium to polyselenoureas with long-term stability,good solubility,well-characterized structures,and unique functionalities.The MCPs enjoyed broad monomer scope and fast conversion in 1 min,delivering 18 polyselenoureas with high molecular weights(M_(w)s up to 94,600 g/mol)in high yields(up to 99%).Furthermore,the polyselenoureas could be used for the extraction of Au^(3+)from mixed-metal ion solutions under practical conditions with high selectivity,sensitivity(<1μg/L),efficiency(>99.99%),and capacity(up to 665.60 mg·Au^(3+)/g)within 1 min.Further,the elemental gold was recoverable after the pyrolysis of the polymer complexes.

Catalyst-free multicomponent polymerization of sulfonyl azide,aldehyde and cyclic amino acids toward zwitterionic and amphiphilic poly(N-sulfonyl amidine)as nanocatalyst precursor

Polymers with metal coordination ability are outstanding precursors of nanocatalysts,attracting numerous attention in nanocatalysis area.It has been rarely reported for the poly(N-sulfonyl amidines)as macromolecular ligands for nanocatalysis.Herein,a catalyst-free multicomponent polymerization(MCP)strategy is developed to facilely prepare a library of amphiphilic poly(Nsulfonyl amidines)with zwitterionic properties starting from disulfonyl azide,hydrophilic dialdehyde and cyclic amino acids including proline and pipecolinic acid.Metals or additives can be thorougly avoided through this method.All the obtained polymers have well-defined structures,high yields and weight-average molecular weights(M_(w)s,up to 99,300 g/mol).The unique zwitterionic property,amphiphilicity and Cu(Ⅰ)coordination ability of the obtained poly(N-sulfonyl amidines)endow them to form the polymer-Cu(Ⅰ)complexes as nanocatalysts.Such nanocatalysts exhibit high catalytic efficiency in aqueous Cucatalyzed azide-alkyne cycloaddition(CuAAC)reaction at a low Cu(Ⅰ)loading of 50 ppm.Nanocatalysts with a high ratio of polymers to Cu(Ⅰ)have also been demonstrated with Cu(Ⅰ)stabilization ability.This work provides a“green”MCP method toward zwitterionic and amphiphilic poly(N-sulfonyl amidines),and highlights their unique potentials for nanocatalysis.

In Situ Generation of N-Heteroaromatic Polymers:Metal-Free Multicomponent Polymerization for Photopatterning,Morphological Imaging,and Cr(Ⅵ)Sensing

Electron-deficient N-heteroaromatic polymers are crucial for the high-tech applications of organicmaterials,especially in the electronic and optoelectronic fields.Thus,the development of new polymerizations to afford adaptable electron-donating-accepting scaffolds in N-heteroaromatic polymers is in high demand.Herein,we have developed metal-free multicomponent polymerizations of diynes,diamines,and glyoxylates successfully for in situ generation of poly(quinoline)s with high molecular weights(Mw up to 16,900)in nearly quantitative yields.By tuning the electron distributions of the polymer backbones,the resulting poly(quinoline)s showed various aggregation-induced behaviors and photoresponsive abilities:The thin films of the poly(quinoline)s could be fabricated readily intowell-resolved photopatterns by photolithography techniques.They could be utilized as fluorescent probes to visualize themorphologies of polymer materials directly;these include spherulites and microphase separation of polymer blends.Their nanoparticles demonstrated sensitive and highly selective fluorescence quenching to hexavalent chromium ion Cr(Ⅵ),thereby providing access for biological imaging of Cr(Ⅵ)in unicellular algae.

Diamines,CS2 and Monoisocyanide-participated Polymerizations for Large-scale Synthesis of Polythioureas and Thioformamide

Multicomponent polymerizations(MCPs)are powerful tools to synthesize functional polymers with great structural diversity,low cost and high efficiency,which usually generate single polymer product.Herein,a robust one-pot diamines,CS_(2)and monoisocyanide-participated catalyst-free polymerization was developed at room temperature to produce polythiourea and thioformamide simultaneously in equal equivalent,which was featured with cheap monomers,simple operation and mild condition,affording various polythioureas with high Mws of up to 4.75×10^(4)g/mol in high yields of up to 98%.Polythioureas with varied chain composition and sequence-controlled structure could be synthesized in 62 g-scale from copolymerization or multicomponent tandem polymerization,enabling facile tuning of thermal property,crystallinity,mechanical property,and fluorescence.The abundant irregular hydrogen bonds endowed the polythioureas excellent glassy state self-healing property at room temperature or below 0℃.This polymerization provided an efficient and economic approach to access functional polythioureas.

Two tandem multicomponent reactions for the synthesis of sequence-defined polymers

Multicomponent polymerizations have become powerful tools for the construction of sequence-defined polymers. Although the Passerini multicomponent reaction has been widely used in the synthesis of sequence-defined polymers, the tandem usage of the Passerini multicomponent reaction and other multicomponent reactions in one-pot for the synthesis of sequence-defined polymers has not been developed until now. In this contribution, we report the tandem usage of the Passerini three-component reaction and the three-component amine-thiol-ene conjugation reaction in one pot for the synthesis of sequence-defined polymers. The Passerini reaction between methacrylic acid, adipaldehyde, and 2-isocyanobutanoate was carried out, affording a new molecule containing two alkene units. Subsequently, an amine and a thiolactone were added to the reaction system, whereupon the three-component amine-thiol-ene conjugating reaction occurred to yield a sequence-defined polymer. This method offers more rapid access to sequence-defined polymers with high molecular diversity and complexity.

Three-Component Asymmetric Polymerization toward Chiral Polymer

Chiral-polymers with metal-coordination ability showgreat potential formediating asymmetric reactions.However,the synthesis of structurally diverse chiral polymers remains a great challenge,especially doing so efficiently.Herein,four types of Cucatalyzed multicomponent asymmetric polymerizationswere developed using a flexible combination of OBoc-alkyne.

Green Monomer of CO_(2) and Alkyne-based Four-component Tandem Polymerization toward Regio-and Stereoregular Poly(aminoacrylate)s

Green monomers, such as carbon dioxide(CO_(2)), are closely related to our daily life and highly desirable to be transferred to functional polymers with diverse structures and versatile properties because they are abundant, cheap, nontoxic, renewable, and sustainable. However, the polymerizations based on these green monomers are to be further developed. In this work, a facile CO_(2) and alkyne-based one-pot, two-step, fourcomponent tandem polymerization was successfully established. The polymerization of CO_(2), diynes, alkyl dihalides, and primary/secondary amines can proceed under mild reaction conditions and regio-and stereoregular poly(aminoacrylate)s with good solubility and thermal stability were obtained in high yields(up to 95%). Notably, distinctly different stereoregularity of resultant poly(aminoacrylate)s was realized via using primary or secondary amines. Using the former would readily generate polymers with 100% Z-isomers, whereas the latter furnished products with over 95% E-isomers. Through different monomer combination, the polymers with tunable structures and properties were obtained.Moreover, the tetraphenylethene units containing poly(aminoacrylate)s, showing the unique aggregation-induced emission characteristics,could function as a fluorescent probe for sensitive explosive detection. Thus, this work not only develops a facile CO_(2) and alkyne-based multicomponent tandem polymerization but also provides a valuable strategy to fine-tune the polymer structures and properties, which could be potentially applied in diverse areas.