Recent Developments in Functional Polymers via the Kabachnik-Fields Reaction: The State of the Art

Recently, multicomponent reactions (MCRs) have attracted much attention in polymer synthesis. As one of the most well-known MCRs, the Kabachnik-Fields (KF) reaction has been widely used in the development of new functional polymers. The KF reaction can efficiently introduce functional groups into polymer structures; thus, polymers prepared via the KF reaction have unique α-aminophosphonates and show important bioactivity, metal chelating abilities, and flame-retardant properties. In this mini-review, we mainly summarize the latest advances in the KF reaction to synthesize functional polymers for the preparation of heavy metal adsorbents, multifunctional hydrogels, flame retardants, and bioimaging probes. We also discuss some emerging applications of functional polymers prepared by means of the KF reaction. Finally, we put forward our perspectives on the further development of the KF reaction in polymer chemistry.

Superhydrophobic Coatings Composed of Multifunctional Polymers Synthesized Using Successive Modification of Dihydropyrimidin-2(1H)-thione

Polymer synthesis via multicomponent reactions (MCRs) has opened avenues in polymer chemistry and led to the development of various types of functional polymers. Herein, we developed a strategy to prepare multifunctional polymers via the successive modification of dihydropyrimidin-2(1H)-thione (DHPMT), which can be generated by the tricomponent Biginelli reaction. Four hydrophobic polymers were efficiently prepared by using DHPMT derivatives. These polymers can be dip-coated onto the oxidized copper mesh to obtain superhydrophobic meshes because of the strong attractive forces between the DHPMT derivatives and Cu(II). The optimized mesh has self-cleaning properties and outstanding stability in various liquid environments; it has also been successfully applied for oil/water separation with high separation efficiency and good durability. These results demonstrate that successive modification of DHPMT is a promising method for fabricating multifunctional polymers, which may have applications in polymer chemistry and materials science.

Multicomponent Synthesis of Poly(α-aminophosphine chalcogenide)s and Subsequent Depolymerization

Multicomponent reactions of primary phosphines (R-PH2), diimines (R'-N═C(H)-R-(H)C═N-R'), and chalcogens (O2, S8) generate poly(α-aminophosphine chalcogenide)s (4-7) through step-growth polymerization. Characterization of the linear polymers using 31P{1H} diffusion-ordered NMR spectroscopy (DOSY) experiments aided in determining the molecular weight (Mw) of the material. Subjecting the polyphosphine oxide or sulfide to reducing conditions in the presence of a Lewis acid resulted in complete depolymerization of the polymers, quantitatively releasing the 1° phosphine and diimine (2) starting materials, with concomitant reduction of diimine to diamine (9).

Poly(vinyl alcohol) Modified via the Hantzsch Reaction for Biosafe Antioxidant Self-Healing Hydrogel

Efficient routes for the preparation of functional self-healing hydrogels from functional polymers are needed. In this study, we developed a strategy to effectively produce a vanillin-modified poly(vinyl alcohol) (PVA-vanillin) through the Hantzsch reaction. This polymer was cross-linked with a phenylboronic acid-containing polymer (PB) that was also prepared using the Hantzsch reaction to fabricate a hydrogel through borate ester linkages under mild conditions (25 °C, pH ∼ 7.4). This hydrogel had excellent antioxidant abilities due to the 1,4-dihydropyridine (DHP) rings and the vanillin moieties in the hydrogel structures; it was also self-healable and injectable owing to the dynamic borate ester linkages. Furthermore, the antioxidant self-healing hydrogel had low cytotoxicity and exhibited favorable safety in animal experiments, indicating its potential as a safe implantable cell or drug carrier. This study developed a method for preparing functional polymers and related self-healing hydrogels in a facile manner; it demonstrated the value of the Hantzsch reaction in exploiting antioxidant self-healing hydrogels for biomedical applications, which may provide insight into the design of other functional self-healing hydrogels through different multicomponent reactions.

Synthesis and Characterization of a New Series of Bis(allylic-α-aminophosphonates) under Mild Reaction Conditions

Several bis(α-aminophosphonates) have been conveniently prepared in good yields using a straightforward multicomponent Kabachnik-Fields reaction between ethane 1,2-diamine or propane 1,3-diamine, diethylphosphite and aldehydes under catalyst-free conditions. The nucleophilic substitution reaction of bis(α-aminophosphonates) prepared and ethyl (2-bromomethyl)acrylate under mild reaction conditions afforded an original synthetic approach to a new series of bis(allylic-α-aminophosphonates).

In-Capillary Photodeposition of Glyphosate-Containing Polyacrylamide Nanometer-Thick Films

The present research reports on in-water, site-specific photodeposition of glyphosate (GLP)-containing polyacrylamide (PAA-GLP) nanometer-thick films (nanofilms) on an inner surface of fused silica (fused quartz) microcapillaries presilanized with trimethoxy(octen-7-yl)silane (TMOS). TMOS was chosen because of the vinyl group presence in its structure, enabling its participation in the (UV light)-activated free-radical polymerization (UV-FRP) after its immobilization on a fused silica surface. The photodeposition was conducted in an aqueous (H₂O/ACN; 3:1, v/v) solution, using UV-FRP (λ = 365 nm) of the acrylamide (AA) functional monomer, the N,N'-methylenebis(acrylamide) (BAA) cross-linking monomer, GLP, and the azobisisobutyronitrile (AIBN) UV-FRP initiator. Acetonitrile (ACN) was used as the porogen and the solvent to dissolve monomers and GLP. Because of the micrometric diameters of microcapillaries, the silanization and photodeposition procedures were first optimized on fused silica slides. The introduction of TMOS, as well as the formation of PAA and PAA-GLP nanofilms, was determined using atomic force microscopy (AFM), scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) spectroscopy, and confocal micro-Raman spectroscopy. Particularly, AFM and SEM-EDX measurements determined nanofilms' thickness and GLP content, respectively, whereas in-depth confocal (micro-Raman spectroscopy)-assisted imaging of PAA- and PAA-GLP-coated microcapillary inner surfaces confirmed the successful photodeposition. Moreover, we examined the GLP impact on polymer gelation by monitoring hydration in a hydrogel and a dried powder PAA-GLP. Our study demonstrated the usefulness of the in-capillary micro-Raman spectroscopy imaging and in-depth profiling of GLP-encapsulated PAA nanofilms. In the future, our simple and inexpensive procedure will enable the fabrication of polymer-based microfluidic chemosensors or adsorptive-separating devices for GLP detection, determination, and degradation.

Stepping Further from Coupling Tools: Development of Functional Polymers via the Biginelli Reaction

Multicomponent reactions (MCRs) have been used to prepare polymers with appealing functions. The Biginelli reaction, one of the oldest and most famous MCRs, has sparked new scientific discoveries in polymer chemistry since 2013. Recent years have seen the Biginelli reaction stepping further from simple coupling tools; for example, the functions of the Biginelli product 3,4-dihydropyrimidin-2(1H)-(thi)ones (DHPM(T)) have been gradually exploited to develop new functional polymers. In this mini-review, we mainly summarize the recent progress of using the Biginelli reaction to identify polymers for biomedical applications. These polymers have been documented as antioxidants, anticancer agents, and bio-imaging probes. Moreover, we also provide a brief introduction to some emerging applications of the Biginelli reaction in materials and polymer science. Finally, we present our perspectives for the further development of the Biginelli reaction in polymer chemistry.

Magnetic Self-Healing Hydrogel from Difunctional Polymers Prepared via the Kabachnik-Fields Reaction

The development of high quality magnetic self-healing hydrogels containing well-dispersed magnetic nanoparticle has been a challenging procedure due to unavailable methods of facilely introducing groups that can efficiently stabilize these magnetic nanoparticles in the self-healing hydrogels. In this research, a polymer containing both phenylboronic acid (PBA) and phosphonic acid (PA) groups has been developed by the Kabachnik-Fields (KF) reaction. This polymer well disperses iron oxide nanoparticles (IONPs) through the strong interactions between the PA groups and the surface of the IONPs; thus, this polymer effectively mixed IONPs and poly(vinyl alcohol) (PVA) to form a hydrogel containing well-dispersed IONPs. The resulting hydrogel is self-healing, owing to the dynamic borate ester linkages. Moreover, the presence of the IONPs endowed the hydrogel with magnetic properties, also making it heat-responsive in an alternating magnetic field and expanding its application as a contrast agent for magnetic resonance imaging. The magnetic self-healing hydrogel showed excellent biosafety properties in animal experiments, suggesting its potential as an injectable implant material for biological and medical applications. This research exploits a biocompatible magnetic self-healing hydrogel with well-dispersed IONPs, demonstrating the value of the KF reaction in the development of functional polymers and smart materials, which might prompt a broad study of multicomponent reactions in interdisciplinary fields.

Introducing the aza-Michael addition reaction between acrylate and dihydropyrimidin-2(1H)-thione into polymer chemistry

The aza-Michael addition reaction between dihydropyrimidin-2(1H)-thione and acrylate has been used to fabricate new polymers through different synthesis routes.

Modulating the reactivity of polymer with pendant ester groups by methylation reaction for preparing functional polymers

Chemical reaction triggered the reactivity of polymeric esters.

Tandem polymerization consisting of cyclotrimerization and the Tishchenko reaction: synthesis of acid- and alkali-degradable polymers with cyclic acetal and ester structures in the main chain

Tandem polymerization consisting of cyclotrimerization and the Tishchenko reaction was developed, which yielded acid- and alkali-degradable polymers.

De Novo Design of Entropy-Driven Polymers Resistant to Bacterial Attachment via Multicomponent Reactions

Nonbactericidal polymers that prevent bacterial attachment are important for public health, environmental protection, and avoiding the generation of superbugs. Here, inspired by the physical bactericidal process of carbon nanotubes and graphene derivatives, we develop nonbactericidal polymers resistant to bacterial attachment by using multicomponent reactions (MCRs) to introduce molecular "needles" (rigid aliphatic chains) and molecular "razors" (multicomponent structures) into polymer side chains. Computer simulation reveals the occurrence of spontaneous entropy-driven interactions between the bacterial bilayers and the "needles" and "razors" in polymer structures and provides guidance for the optimization of this type of polymers for enhanced resistibility to bacterial attachment. The blending of the optimized polymer with commercially available polyurethane produces a film with remarkably superior stability of the resistance to bacterial adhesion after wear compared with that of commercial mobile phone shells made by the Sharklet technology. This proof-of-concept study explores entropy-driven polymers resistant to bacterial attachment via a combination of MCRs, computer simulation, and polymer chemistry, paving the way for the de novo design of nonbactericidal polymers to prevent bacterial contamination.

Sequential Post-Polymerization Modification of Aldehyde Polymers to Ketone and Oxime Polymers

A new sequential post-polymerization modification route has been developed for the synthesis of multifunctional polymers from a simple aldehyde polymer. In the first modification step, a template polymer derived from the radical polymerization of 4-vinyl benzaldehyde undergoes Rh-catalyzed hydroacylation with alkenes to furnish a group of ketone polymers. In the second modification step, Schiff base formation with alkoxy ammonium salts introduces a second group-an oxime functionality. Both the steps are highly efficient, introducing evenly distributed dual functionalities at the same position.

Synthesis of α-Aminophosphonates and Related Derivatives; the Last Decade of the Kabachnik-Fields Reaction

The Kabachnik-Fields reaction, comprising the condensation of an amine, oxo compound and a P-reagent (generally a >P(O)H species or trialkyl phosphite), still attracts interest due to the challenging synthetic procedures and the potential biological activity of the resulting α-aminophosphonic derivatives. Following the success of the first part (Molecules 2012, 17, 12821), here we summarize the synthetic developments in this field accumulated in the last decade. The procedures compiled include catalytic accomplishments as well as catalyst-free and/or solvent-free "greener" protocols. The products embrace α-aminophosphonates, α-aminophosphinates, and α-aminophosphine oxides along with different bis derivatives from the double phospha-Mannich approach. The newer developments of the aza-Pudovik reactions are also included.

Stimuli-Responsive Multifunctional Phenylboronic Acid Polymers Via Multicomponent Reactions: From Synthesis to Application

Stimuli-responsive polymers undergo changes under different environmental conditions. Among them, phenylboronic acid (PBA) containing polymers (PBA-polymers) are unique, because they can selectively react with diols to generate borates that are sensitive to pH, sugars, and H₂ O₂ , and can be effectively used to synthesize smart drug carriers and self-healing hydrogels. Recently, multifunctional PBA-polymers (MF-PBA-polymers) have been developed using multicomponent reactions (MCRs) to introduce PBA groups into polymer structures. These MF-PBA-polymers have features similar to those of traditional PBA-polymers; moreover, they exhibit additional properties, such as fluorescence, antimicrobial activity, and antioxidant capability, when different MCRs are used. In this mini review, the preparation of these MF-PBA-polymers are summarized and the new properties/functions that have been introduced into these polymers using different MCRs are discussed. The uses of these MF-PBA-polymers as fluorescent cell anticoagulants, drug carriers, and gelators of functional self-healing hydrogels have been discussed. Additionally, the challenges encountered during their preparation are discussed and also the future developments in this field are touched upon.

Multicomponent Reactions in Polymer Chemistry Utilizing Heavier Main Group Elements

Herein, a concise overview of the use of heavier main group elements in multicomponent reactions and their use in polymer chemistry is provided. Incorporating heavier elements into macromolecular structures via multicomponent reactions allows for the rapid development of materials with unique properties that are not readily achieved using carbon, nitrogen, and/or oxygen. Elements in Group 13, Group 14, Group 15, and Group 16 are specifically covered examining both the familiar and unfamiliar properties of these elements and how they are used in multicomponent chemistry. Furthermore, elements that both take part in the reaction mechanism and remain in the macromolecular structure upon completion are only briefly explored. Some of the state-of-the-art work going into developing these heavier element multicomponent reactions are highlighted and it is hoped to inspire other polymer chemists to explore other parts of the periodic table.

The Hantzsch Reaction in Polymer Chemistry: From Synthetic Methods to Applications

The Hantzcsh reaction is a robust four-component reaction for the efficient generation of 1,4-dihydropyridine (1,4-DHP) derivatives. Recently, this reaction has been introduced into polymer chemistry in order to develop polymers having 1,4-DHP structures in the main and/or side chains. The 1,4-DHP groups confer new properties/functions to the polymers. This mini-review summarizes the recent studies on the development of new functional polymers by using the Hantzsch reaction. Several synthetic approaches, including polycondensation, post-polymerization modification (PPM), monomer to polymer strategy, and one-pot strategy are introduced; different applications (protein conjugation, formaldehyde detection, drug carrier, and anti-bacterial adhesion) of the resulting polymers are emphasized. Meanwhile, the future development of the Hantzsch reaction in exploring new functional polymers is also discussed.

Antioxidant Polymers via the Kabachnik-Fields Reaction to Control Cellular Oxidative Stress

Small molecular antioxidants are almost ineffective in regulating harmful oxidative stress in vivo because of their poor bioavailability. Polymer antioxidants are a promising alternative to address this issue, but their laborious synthetic routes limit their development. In this study, aliphatic and aromatic aldehydes are used to synthesize a family of polymers containing different α-aminophosphonate pendant groups via a facile one-pot method that combines the Kabachnik-Fields (KF) reaction and free radical polymerization. The structure-property relationship study of these polymers reveals the KF moieties in polymer structures confer radical scavenging ability on polymers. The radical scavenging ability and cytotoxicity of these polymers are evaluated in a stepwise manner to identify a biocompatible polymer antioxidant that can effectively protect the cells from H₂ O₂ -induced oxidative damage. This is the first attempt to develop antioxidative polymers by the KF reaction. It highlights the feasibility of synthesizing new functional polymers using multicomponent reactions, which has important implications for organic and polymer chemistry.

Anticancer Polymers via the Biginelli Reaction

We developed a polymer-drug strategy to explore anticancer polymers. A series of monomers containing groups with potential anticancer activity have been facilely prepared through the Biginelli reaction. These monomers were used to produce water-soluble polymers through convenient radical copolymerization. The resulting polymers are biocompatible and can be directly used to suppress proliferation of different cancer cells without the release of small molecules. Theoretical calculations revealed that Biginelli groups in polymers had strong interaction with the Eg5 protein, which is highly expressed in cancer cells and is closely related to cell mitosis. Subsequent cell experiments confirmed that a screened polymer is efficient in inhibiting mitosis in different cancer cells. Our study of exploring functional polymers via the combination of multicomponent reactions and theoretical calculation resulted in promising anticancer polymers, which might pave a path for de novo designing of functional polymers and have important implications in the fields of organic, computational, and polymer chemistry.

Using One Photoredox Catalyst to Simultaneously Mediate Two Different Polymerizations for Photo-Triggered Multi-Component Orthogonal Polymerizations

The development of multi-component orthogonal polymerizations (MOPs) with simple procedure and high efficiency is crucial for rational polymer synthesis. In this work, photo-triggered Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) polymerization are first investigated, employing copper(II) thioxanthone carboxylate (Cu(TX)₂ ) as photoredox catalyst and sunlight as stimuli. Then, the novel MOPs using one photoredox catalyst, Cu(TX)₂ to simultaneously mediate two different photopolymerizations, are successfully realized in one-pot, where photo-induced electron transfer atom transfer radical polymerization and photo-activated CuAAC polymerization can effectively proceed in a one-pot and non-interfering fashion to afford predetermined copolymers with well-defined structure.

High-Throughput Preparation of Antibacterial Polymers from Natural Product Derivatives via the Hantzsch Reaction

The Hantzsch and free-radical polymerization reactions were combined in a one-pot high-throughput (HTP) system to simultaneously prepare 30 unique polymers in parallel. Six aldehydes derived from natural products were used as the starting materials to rapidly prepare the library of 30 poly(1,4-dihydropyridines). From this library, HTP evaluation methods led to the identification of an antibacterial polymer. Mechanistic studies revealed that the dihydropyridine group in the polymer side-chain structure plays an important role in resisting bacterial attachment to the polymer surface, thus leading to the antibacterial function of this polymer. This research demonstrates the value of multicomponent reactions (MCRs) in interdisciplinary fields by discovering functional polymers for possible practical applications. It also provides insights to further developing new functional polymers using MCRs and HTP methods with important implications in organic chemistry, polymer chemistry, and materials science.

Multicomponent Radziszewski Emulsion Polymerization toward Macroporous Poly(ionic liquid) Catalysts

Interconnected macroporous imidazolium-based monoliths are produced via the modified Radziszewski multicomponent reaction (MCR) applied to triamines under high internal phase emulsion (HIPE) conditions. This straightforward one-pot synthesis combines the efficiency and versatility of MCRs with the ease of implementation of the emulsion templating polymerization process. The characterization of the chemical structure and morphology of the resulting materials confirms the formation of the expected macroporous poly(ionic liquid)s (PILs) networks. The promising catalytic activity and recyclability of these porous PIL monoliths are illustrated for the transesterification reaction and the decarboxylation of caffeic acid. In these cases, almost complete conversion is reached while benefiting from the advantages associated with a heterogeneous catalyst.

A Facile Preparation of Mussel-Inspired Poly(dopamine phosphonate-co-PEGMA)s via a One-Pot Multicomponent Polymerization System

Mussel-inspired polymers attract much research interest due to their potential as effective adhesives. In this work, a new kind of mussel-inspired polymer, poly(dopamine phosphonate-co-PEGMA), is prepared via a one-pot multicomponent polymerization system. The multicomponent polymerization system refers to a combination of multicomponent Kabachnik-Fields (KF) reaction and reversible addition-fragmentation chain transfer (RAFT) polymerization system. Reactants are converted to dopamine phosphonate monomers in situ through the KF reaction and polymerized simultaneously along with poly(ethylene glycol methyl ether) methacrylate (PEGMA) co-monomers by the RAFT process in a one-pot operation. Target polymers with dopamine phosphonate as side groups and well-defined polymer structures are thus facilely and successfully prepared. Afterwards, a series of polymers with various ratios of dopamine phosphonates as well as the crosslinked polymer analogues are prepared. Benefiting from the dopamine phosphonate side groups, aqueous solutions of those polymers show potential as effective adhesives in both dry and wet conditions, and their adhesive strengths are highly related to ratios of dopamine phosphonates in the polymers. Those polymers are non-cytotoxic and show strong bonding affinities on various substrates including metals, polymers, and bovine bones, suggesting their potential as environmentally friendly general adhesives in broad areas.

Ugi Three-Component Polymerization Toward Poly(α-amino amide)s

Due to their great modularity, ease of implementation, and atom economy, multicomponent reactions (MCRs) are becoming increasingly popular macromolecular engineering tools. In this context, MCRs suitable in polymer synthesis are eagerly searched for. This work demonstrates the potential of the Ugi-three component reaction (Ugi-3CR) for the design of polymers and, in particular, of poly(α-amino amide)s. A series of polymers containing amino and amido groups within their backbone were obtained through a one-pot process by reacting aliphatic or aromatic diamines, diisocyanides, and aldehydes. The impact of temperature, concentration, catalyst loading, and substrates on polymerization efficiency is discussed. A preliminary study on the thermal properties and the solution behavior of these poly(α-amino amide)s was carried out. An aliphatic-rich derivative notably showed some pH-responsiveness in water via protonation-deprotonation of its amino groups.

A polymerizable aggregation-induced emission dye for fluorescent nanoparticles: synthesis, molecular structure and application in cell imaging

This work reports the fabrication of a novel polymerizable AIE dye and its amphiphilic PEG-TS fluorescent polymers via RAFT polymerization, which were attractive for the application in cell imaging.

High Throughput Preparation of UV-Protective Polymers from Essential Oil Extracts via the Biginelli Reaction

A high throughput (HTP) system has been developed to exploit new functional polymers. We synthesized 25 monomers in a mini-HTP manner through the tricomponent Biginelli reaction with high yields. The starting materials were five aldehydes extracted from essential oils. The 25 corresponding polymers were conveniently prepared via mini-HTP radical polymerization initially realizing the benefit of HTP methods to quickly fabricate sample libraries. The distinct radical scavenging ability of these Biginelli polymers was evaluated through a HTP measurement to choose the three best radical scavengers. This confirms the superiority of the HTP strategy to rapidly collect and analyze data. The selected polymers have been upgraded and screened according to different requirements for biomaterials and offer water-soluble and biocompatible copolymers that effectively protect cells from the fatal UV damage. This research is a straightforward way to establish new libraries of monomers with abundant diversity. It offers polymers with interesting functionalities. This suggests that a broader study of multicomponent reactions and HTP methods might be useful in many interdisciplinary fields. To the best of our knowledge, this is the first report of a HTP study of the Biginelli reaction to develop a promising polymeric biomaterial, which might have important implications for the organic chemistry and polymer communities.

Fluorescent Cell-Conjugation by a Multifunctional Polymer: A New Application of the Hantzsch Reaction

Multicomponent reactions (MCRs) can form unique structures with interesting functions, therefore, multifunctional polymers might be simply prepared using MCRs as coupling tools to simultaneously link and generate different functional groups. To verify this concept, a new fluorescent polymer containing phenylboronic acid has been facilely prepared via a one pot method by combining the Hantzsch reaction with reversible addition-fragmentation chain transfer (RAFT) polymerization. The Hantzsch-RAFT system has been found robust to smoothly achieve predesigned multifunctional polymer, which can be used for cell conjugation through the interaction between phenylboronic acid and glycoprotein on cell membrane. The conjugated cells could be directly observed due to the fluorescent Hantzsch moiety in the polymer chain, demonstrating a new application of the old Hantzsch reaction (>130 years) outside organic chemistry. Meanwhile, the conjugated cells remained excellent dispersity in the presence of coagulation protein (lectin), implying that multifunctional polymer a possible anticoagulant for cell separation. We believe that the current research paves a new way to exploit new applications of MCRs in interdisciplinary fields and might prompt the development of other multifunctional polymers based on different MCRs.

Ultrasonic-assisted Kabachnik-Fields reaction for rapid fabrication of AIE-active fluorescent organic nanoparticles

Aggregation-induced emission (AIE)-active fluorescent organic nanoparticles (FNPs) have been extensively explored for fluorescence "turn-on" bio-imaging applications with the unique advantages over conventional FNPs. Transformation of AIE-active molecules into FNPs can greatly expand their biomedical application potential. Here we reported a novel "one-pot" strategy for fabricating AIE-active FNPs through an ultrasonic-assisted, catalysts-free and solvent-free Kabachnik-Fields (KF) reaction for the first time. The KF reaction can be completed within 10min to generate AIE-active PTH-CHO-PEI-DEP FNPs through mixing polyethylenimine and aldehyde group containing AIE dyes and diethyl phosphate. These PTH-CHO-PEI-DEP FNPs were confirmed by proton nuclear magnetic resonance (¹H NMR) spectroscopy, transmission electron microscopy (TEM) and fluorescence spectroscopy etc. The cell uptake behavior as well as cell viability of PTH-CHO-PEI-DEP FNPs was examined to evaluate their potential for biomedical application. We demonstrated that the amphiphilic α-aminophosphonate polymers could self-assemble into PTH-CHO-PEI-DEP FNPs in aqueous solution and showed excellent water dispersibility. TEM image shows the size of PTH-CHO-PEI-DEP FNPs is 100-200nm. More importantly, the PTH-CHO-PEI-DEP FNPs emit strong green fluorescence and desirable biocompatibility, making them very suitable for biomedical applications. Finally, thus smart FNPs design together with their excellent performance will open a new avenue in the development of FNPs for following biological processes such as carcinogenesis.

Marrying multicomponent reactions and aggregation-induced emission (AIE): new directions for fluorescent nanoprobes

Recent development and progress for fabrication and applications of aggregation-induced emission polymers through multicomponent reactions have been summarized in this review.

Post-polymerization modification via the Biginelli reaction to prepare water-soluble polymer adhesives

A copolymer precursor containing the β-ketoester moiety has been modified through the Biginelli reaction to get several water-soluble adhesives which are comparable to commercial glues.

The Hantzsch reaction in polymer chemistry: synthesis and tentative application

The recent utilization of the tetra-component Hantzsch reaction in polymer chemistry has been summarized.

Multicomponent Combinatorial Polymerization via the Biginelli Reaction

A multicomponent combinatorial polymerization method has been exploited as a new intersection between combinatorial chemistry, polymer chemistry, and organic chemistry. The tricomponent Biginelli reaction has been employed as a model multicomponent reaction (MCR) to efficiently prepare a library of polycondensates with continuously changed chain structure but different physical properties. The naturally increased reaction modules (monomers) directly doubled the number of polymers in the library, effectively improving the efficiency of polymer preparation. The glass transition temperatures (Tg) of those homologous polymers have been mapped for the first time to predict the Tg values of absent polymer homologues with good to excellent accuracy. Meanwhile, the Tg maps have also been used to reveal the regular change in Tg according to the polymer structure (linking group, monomer chain length, etc.), initially suggesting the academic significance of the multicomponent combinatorial polymerization system. We believe that the current research paves a straightforward way to synthesize new libraries of polymers via MCRs and might prompt the broader study of MCRs in interdisciplinary fields.

Facile synthesis of a multifunctional copolymer via a concurrent RAFT-enzymatic system for theranostic applications

Through a straightforward concurrent RAFT-enzymatic multicomponent polymerization system and subsequent post-polymerization modifications, a multi-functional copolymer for theranostic application has been efficiently prepared.