Synthesis and Characterization of a Thermoresponsive Polyoxometalate–Polymer Hybrid

We report the synthesis of the first organo‐POM with thermoresponsive properties. Our concept will provide chemists with a new tool to design POMs whose solubility is reversibly controllable through an external stimulus. POM–polymer TBA₇[POM]‐poly(N,N‐diethylacrylamide) (POM–PDEAAm), was prepared by grafting PDEAAm‐NH₂ (obtained by RAFT polymerization) onto the activated Dawson acyl‐POM, α₂‐[P₂W₁₇O₆₁SnCH₂CH₂C(?O)]^6?. Extensive MS analysis was used to monitor the chain‐functionalization steps and to confirm the formation of the hybrid. Aqueous solutions of the (NH₄)₇[POM–PDEAAm] exhibited a LCST of 38 °C. Thus, the solubility/aggregation of the hybrid was reversibly controlled by changing the temperature. Above 38 °C, the solution became cloudy, and cleared again upon cooling. Dynamic light scattering (DLS) revealed the formation of small aggregates in the range 100 nm. We assumed that the charged POM head units prevented the formation of the larger‐scattering aggregates that are usually observed for PDEAAm, and promoted the formation of micelle‐like structures. The conjugate exhibited a temperature transition, which was different from that of the polymer and depended on the counterions associated with the POM. This result demonstrates the potential for merging organic (in this case, polymer) and inorganic structures to afford materials that exhibit new properties.     

A New Class of Tunable Dendritic Diphosphine Ligands: Synthesis and Applications in the Ru‐Catalyzed Asymmetric Hydrogenation of Functionalized Ketones

A series of tunable G₀–G₃ dendritic 2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl (BINAP) ligands was prepared by attaching polyaryl ether dendrons onto the four phenyl rings on the P atoms. Their ruthenium complexes were employed in the asymmetric hydrogenation of β‐ketoesters, α‐ketoesters, and α‐ketoamides to reveal the effects of dendron size on the catalytic properties. The second‐ and third‐generation catalysts exhibited excellent enantioselectivities, which are remarkably higher than those obtained from the small molecular catalysts and the first‐generation catalyst. Molecular modeling indicates that the incorporation of bulky dendritic wedges can influence the steric environments around the metal center. In addition, the ruthenium catalyst bearing a second‐generation dendritic ligand could be recycled and reused seven times without any obvious decrease in enantioselectivity.     

Water‐soluble dendritic‐conjugated polyfluorenes: Synthesis,characterization, and interactions with DNA

Three generation of Boc‐protected dendritic‐conjugated polyfluorenes ( Boc‐PFP‐G_0‐2 ) were synthesized by Suzuki coupling 1,4‐phenyldiboronic ester with dendritic monomers that were synthesized through generation‐by‐generation approach. The gel permeation chromatography (GPC) analyses showed that the weight‐average molecular weight (M_w) of Boc‐PFP‐G_0‐2 was in the range of 11,400–20,400 Da with the polydispersity index (PDI) in the range of 1.32–1.96. Treatment of Boc‐protected polymers with 6 M HCl in dioxane yielded cationic dendritic‐conjugated polyfluorenes ( PFP‐G_0‐2 ). They were soluble in common polar solvents such as DMSO, DMF, and water with absorption maxima between 345 and 379 nm. The solutions of PFP‐G_0‐2 in water were highly fluorescent with emission maxima between 416 and 425 nm. Because higher generation dendrons could prevent the formation of π‐stacking aggregates of backbones of conjugated polymer, the fluorescence quantum efficiencies (QEs) of PFP‐G_0‐2 enhance as the dendritic generation grew. The interactions between 25 mer double‐stranded DNA (dsDNA) and PFP‐G_0‐2 were studied using ethidium bromide (EB) as fluorescent probe. The electrostatic bindings of PFP‐G_0‐2 with dsDNA/EB complex result in displacement of EB from DNA double helix to the solution accompanying by a quenching of EB fluorescence. The PFP‐G₂ with highest generation of dendritic side chains possessed a highest charge density and could form most stable complex with dsDNA. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7462–7472, 2008     

Controlled aggregation behavior of thermoresponsive polymeric micelles by introducing hydrophilic segments as corona components

Poly[N‐isopropylacrylamide‐co‐N‐(3‐methoxypropyl)acrylamide]‐b‐poly(D,L‐lactide) (P(IPAAm‐co‐MPAAm)‐b‐PLA) as a thermoresponsive block copolymer and PMPAAm‐b‐PLA as a nonthermoresponsive block copolymer were co‐assembled into thermoresponsive polymeric micelles in water. In addition, PMPAAm‐b‐P(IPAAm‐co‐MPAAm)‐b‐PLA triblock copolymer was assembled to form thermoresponsive micelles with a hydrophilic layer on the outermost surface of the thermoresponsive corona. Using both micelles, we investigated the effects of introducing hydrophilic polymer segments on micellar aggregation behavior at temperatures above the lower critical solution temperature (LCST) of the thermoresponsive micelles. Despite the external hydrophilic PMPAAm layer on PMPAAm‐b‐P(IPAAm‐co‐MPAAm)‐b‐PLA micelles, aggregation following dehydration of the thermoresponsive segments was not significantly suppressed at temperatures above the LCST due to the instability of the core‐corona state. In contrast, intermicellar aggregation was successfully controlled by blending P(IPAAm‐co‐MPAAm) and PMPAAm in the thermoresponsive corona region, even above the LCST. In particular, PMPAAm chains longer than the P(IPAAm‐co‐MPAAm) chains could regulate the hydrodynamic diameter of micellar aggregates at temperatures above the LCST. The micelles showed enhanced drug release rates in response to temperature changes above the LCST without precipitating from solution. These results indicated that a side‐by‐side structure of hydrophilic/thermoresponsive chains in the corona region could effectively control the micellar aggregation state after a thermal phase transition. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1695–1704     

Water‐soluble,thermoresponsive, hyperbranched copolymers based on PEG‐methacrylates: Synthesis,characterization, and LCST behavior

A series of water‐soluble thermoresponsive hyperbranched copoly(oligoethylene glycol)s were synthesized by copolymerization of di(ethylene glycol) methacrylate (DEG‐MA) and oligo(ethylene glycol) methacrylate (OEG‐MA, M_w = 475 g/mol), with ethylene glycol dimethacrylate (EGD‐MA) used as the crosslinker, via reversible addition fragmentation chain transfer polymerization. Polymers were characterized by size exclusion chromatography and nuclear magnetic resonance analyses. According to the monomer composition, that is, the ratio of OEG‐MA: DEG‐MA: EGD‐MA, the lower critical solution temperature (LCST) could be tuned from 25 °C to 90 °C. The thermoresponsive properties of these hyperbranched copolymers were studied carefully and compared with their linear analogs. It was found that molecular architecture influences thermoresponsive behavior, with a decrease of around 5–10 °C in the LCST of the hyperbranched polymers compared with the LCST of linear chains. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2783–2792, 2010     

Synthesis of poly(pyridylthioether) dendrimers incorporating a Fe2(CO)6 cluster core

New pyridylthioether-based dendrons bearing a thiol moiety at their focal point have been prepared by a convergent synthetic approach. These dendrons were readily attached to a Fe₂(CO)₆ core to generate two-directional dendritic molecules incorporating an iron-carbonyl cluster.     

Lewis Acid Guests in a {P8W48} Archetypal Polyoxotungstate Host: Enhanced Proton Conductivity via Metal‐Oxo Cluster within Cluster Assemblies

Complexes made by hosts that completely surround their guests provide a means to stabilize reactive chemical intermediates, transfer biologically active cargo to a diseased cell, and construct molecular‐scale devices. By the virtue of inorganic host–guest self‐assembly, nucleation processes in the cavity of a {P₈W₄₈}‐archetype phosphotungstate has afforded a nanoscale 16‐Al^III‐32‐oxo cluster and its Ga^III analogue that contain the largest number of Al^III/Ga^III ions yet found in polyoxometalate (POM) chemistry. Interestingly, the rich Lewis acid Al^III centers within the Lewis base POM support shows an exceptional proton conductivity of 4.5×10^?2 S cm^?1 (85 °C, 70 % RH; RH: relative humidity), which is by far the highest conductivity reported among POM‐based single‐crystal proton conductors.     

Multifunctional Supramolecular Dendrimers with an s‐Triazine Ring as the Central Core: Liquid Crystalline,Fluorescence and Photoconductive Properties

Novel liquid crystal (LC) dendrimers have been synthesised by hydrogen bonding between an s‐triazine as the central core and three peripheral dendrons derived from bis(hydroxymethyl)propionic acid. Symmetric acid dendrons bearing achiral promesogenic units have been synthesised to obtain 3:1 complexes with triazine that exhibit LC properties. Asymmetric dendrons that combine the achiral promesogenic unit and an active moiety derived from coumarin or pyrene structures have been synthesised in order to obtain dendrimers with photophysical and electrochemical properties. The formation of the complexes was confirmed by IR and NMR spectroscopy data. The liquid crystalline properties were investigated by differential scanning calorimetry, polarising optical microscopy and X‐ray diffractometry. All complexes displayed mesogenic properties, which were smectic in the case of symmetric dendrons and their complexes and nematic in the case of asymmetric dendrons and their dendrimers. A supramolecular model for the lamellar mesophase, based mainly on X‐ray diffraction studies, is proposed. The electrochemical behaviour of dendritic complexes was investigated by cyclic voltammetry. The UV/Vis absorption and emission properties of the compounds and the photoconductive properties of the dendrons and dendrimers were also investigated     

Four‐Shell Polyoxometalates Featuring High‐Nuclearity Ln26 Clusters: Structural Transformations of Nanoclusters into Frameworks Triggered by Transition‐Metal Ions

A series of polyoxometalates (POMs) that incorporate the highest‐nuclearity Ln clusters that have been observed in such structures to date (Ln₂₆ , Ln=La and Ce) are described, which exhibit giant multishell configurations (Ln⊂W₆⊂Ln₂₆⊂W₁₀₀). Their structures are remarkably different from known giant POMs that feature multiple Ln ions. In particular, the incorporated Ln–O clusters with a nuclearity of 26 are significantly larger than known high‐nuclearity (≤10) Ln–O clusters in POM chemistry. Furthermore, they also contain the largest number of La and Ce centers for any POM reported to date and represent a new kind of rare giant POMs with more than 100 W atoms. Interestingly, the La₂₆‐containing POM can undergo a single‐crystal to single‐crystal structural transformation in the presence of various transition‐metal ions, such as Cu²⁺, Co²⁺, and Ni²⁺, from an inorganic molecular nanocluster into an inorganic–organic hybrid extended framework that is built from POM building blocks with even higher‐nuclearity La₂₈ clusters bridged by transition‐metal complexes.     

Tunable Thermoresponsive Pyrrolidone‐Based Polymers from Pyroglutamic Acid,a Bio‐Derived Resource

A series of pyrrolidone‐based polymers is prepared from pyroglutamic acid, a bio‐derived resource. Polymers bearing simple alkoxy substituents (e.g., methoxy, ethoxy, and butoxy) are soluble in common organic solvents and possess glass transition temperatures that are dependent on the length of the alkoxy residue. Replacing these substituents with an ether moiety (CH₃OCH₂CH₂O—) affords a highly sensitive and reversible thermoresponsive polymer with a lower critical solution temperature (LCST) of 42 °C in water. Copolymers composed of repeat units bearing both the ether and simple alkoxy residues are found to exhibit LCSTs that are highly dependent on the nature of the hydrophobic alkoxy residue suggesting that the LCSTs of these polymers can be successfully tuned by simply tailoring the copolymer structure.     

Redox‐Controlled Helical Self‐Assembly of a Polyoxometalate Complex

Polyoxometalate (POM) complex (DODA)₂[Mo₆O₁₉] with a symmetrical linear structure was prepared conveniently by replacing the tetrabutylammonium (TBA) counterions of Lindquist‐type cluster (TBA)₂[Mo₆O₁₉] with cationic surfactant dioctadecyldimethylammonium (DODA). A helical self‐assembled structure of the complex was formed in dichloromethane/propanol. The dynamically reversible transformation between helical and spherical assemblies on alternate UV irradiation and H₂O₂ oxidation was characterized by SEM, TEM, and UV/Vis studies. The redox‐controlled morphology change is modulated by variation of the electrostatic interactions between the inorganic polyanion and the organic cation DODA through controlling the redox properties of the POM component, as shown by the XRD, X‐ray photoelectron spectroscopic, and ¹H NMR measurements. The strategy applied herein is a unique example of targeted smart and helical assembly of POM complexes.     

Well‐defined thermoresponsive dendritic polyamide/poly(N‐vinylcaprolactam) block copolymers

The first‐ and second‐generation well‐defined thermoresponsive amphiphilic linear–dendritic diblock copolymers based on hydrophilic linear poly(N‐vinylcaprolactam) and hydrophobic dendritic aromatic polyamide have been synthesized via reversible addition fragmentation chain transfer polymerization of N‐vinylcaprolactam by employing dendritic chain‐transfer agents possessing a single dithiocarbamate moiety at the focal point. These linear–dendritic copolymers exhibit reversible temperature‐dependent phase transition behaviors in aqueous solution as characterized by turbidity measurements using UV–vis spectroscopy. Their lower critical solution temperatures depend on the generation of the dendritic aromatic polyamides and the concentrations of the copolymer solutions. These amphiphilic copolymers are able to form nanospherical micelles in the aqueous solution as revealed by fluorescent spectroscopy, dynamic light scattering, and transmission electron microscope (TEM). The core–shell structure of micelles has been proved by ¹H NMR analyses of the micelles in D2O. The micelles loaded with indomethacin as a model drug showed high‐drug loading capacity and thermoresponsive drug release behavior. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3240–3250     

Self‐Assembly and Structural Evolvement of Polyoxometalate‐Anchored Dendron Complexes

A cationic dendritic molecule that has alkyl chains has been synthesized and employed to encapsulate anionic polyoxometalates through electrostatic interactions. The prepared surfactant‐encapsulated polyoxometalate (SEP) complexes were used as building blocks to fabricate self‐assemblies in solution and the solid state. Monodispersion, lamellar, and columnar assemblies of SEP complexes have been characterized in detail. With increasing the number of peripheral cationic dendrons on inorganic clusters, the SEPs undergo changes from globular assemblies to monodispersions in solution and from lamellar assemblies to hexagonal columnar structures in the solid state, depending on the amounts of cationic dendrons in the complexes. The structural evolvement was simulated through consideration of the size and shape of the cationic dendron and polyanionic clusters, and the experimental results are in good agreement with the interpretation of the simulations. The present research demonstrates a new kind of dendritic complex and provides a route for controlling their assembling states by simply alternating the number of cationic dendrons in the complexes.     

Photoisomerizable and Thermoresponsive N‐isopropylacrylamide–Surfmer Copolymer Hydrogels Prepared upon Electrostatic Self‐Assembly of an Azobenzene Bolaamphiphile

Photoreactive and thermoresponsive N‐isopropylacrylamide (NIPAM)–surfmer copolymer hydrogels containing 4,4′‐di(6‐sulfato‐hexyloxy)azobenzene (DSHA) dianions are described. The functional hydrogels are obtained in a two steps. First a micellar aqueous solution of (11‐(acryloyloxy)undecyl)trimethylammonium bromide (AUTMAB) and NIPAM is exposed to ⁶⁰Co‐gamma irradiation, and a thermoresponsive copolymer gel is obtained. Second, DSHA is included by shrinking the gel at 50 °C and subsequent reswelling in an aqueous solution of DSHA disodium salt at 20 °C. Reswelling is accompanied by electrostatic adsorption of DSHA dianions at the positively charged AUTMAB headgroups replacing the bromide ions. Gels containing trans‐DSHA are transparent yellow at room temperature (λ_max = 370 nm), while gels containing cis‐rich DSHA are orange (λ_max = 460 and 330 nm). Energy dispersive X‐ray measurements indicate that 41% of the bromide ions are exchanged if trans‐DSHA is used for adsorption, and only 7.5% if cis‐DSHA is used. The incorporation of DSHA lowers the lower critical solution temperature (LCST) from 34 to 32 °C. Below the LCST, DSHA can be switched from the trans‐ to the cis‐rich state and vice versa upon irradiation with UV (λ = 366 nm) or visible light (λ ≥ 450 nm). Above the LCST no photoreaction takes place.     

Design and synthesis of "dumb-bell" and "triangular" inorganic-organic hybrid nanopolyoxometalate clusters and their characterisation through ESI-MS analyses

A series of tris(hydroxymethyl)aminomethane (TRIS)‐based linear (bis(TRIS)) and triangular (tris(TRIS)) ligands has been synthesised and were covalently attached to the Wells–Dawson type cluster [P₂V₃W₁₅O₆₂]^9? to generate a series of nanometer‐sized inorganic–organic hybrid polyoxometalate clusters. These huge hybrids, with a molecular mass similar to that of small proteins in the range of ≈10–16 kDa, were unambiguously characterised by using high‐resolution ESI‐MS. The ESI‐MS spectra of these compounds revealed, in negative ion mode, a characteristic pattern showing distinct groups of peaks corresponding to different anionic charge states ranging from 3^? to 8^? for the hybrids. Each peak in these individual groups could be unambiguously assigned to the corresponding hybrid cluster anion with varying combinations of tetrabutylammonium (TBA) and other cations. This study therefore highlights the prowess of the high‐resolution ESI‐MS for the unambiguous characterisation of large, nanoscale, inorganic–organic hybrid clusters that have huge mass, of the order of 10–16 kDa. Also, the designed synthesis of these compounds points to the fact that we were able to achieve a great deal of structural pre‐design in the synthesis of these inorganic–organic hybrid polyoxometalates (POMs) by means of a ligand design route, which is often not possible in traditional “one‐pot” POM synthesis.     

Thermoresponsive Polymer Brush Modulation on the Direction of Motion of Phoretically Driven Janus Micromotors

We report a thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM) brush functionalized Janus Au–Pt bimetallic micromotor capable of modulating the direction of motion with the change of the ambient temperature. The PNIPAM@Au–Pt micromotor moved along the Au–Pt direction with a speed of 8.5 μm s^?1 in 1.5 % H₂O₂ at 25 °C (below the lower critical solution temperature (LCST) of PNIPAM), whereas it changed the direction of motion (i.e., along the Pt–Au direction) and the speed decreased to 2.3 μm s^?1 at 35 °C (above LCST). Below LCST, PNIPAM brushes grafted on the Au side were hydrophilic and swelled, which permitted the electron transfer and proton diffusion on the Au side, and thus the motion is regarded as a self‐electrophoretic mechanism. However, PNIPAM brushes above LCST became hydrophobic and collapsed, and thus the driving mechanism switched to the self‐diffusiophoresis like that of Pt‐modified Janus silica motors. These motors could reversibly change the direction of motion with the transition of the hydrophobic and hydrophilic states of the grafted PNIPAM brushes. Such a thermoresponsive polymer brush functionalization method provides a new strategy for engineering the kinematic behavior of phoretically driven micro/nanomotors.     

Metal(II) Complexes Based on Imidazo[4, 5‐f]‐1, 10‐phenanthroline and Bridging Dicarboxylato Ligands: Synthesis,Characterization and Photoluminescence

Eight metal(II) complexes based on imidazo[4, 5‐f]‐1, 10‐phenanthroline (HIMP) and bridging dicarboxylato ligands such as 4, 4′‐biphenyldicarboxylic acid (H₂BPDC), 1, 4‐benzenedicarboxylic acid (H₂BDC), thiophene‐2, 5‐dicarboxylic acid (H₂TDC), and 2, 6‐naphthalenedicarboxylic acid (H₂NDC) were hydrothermally synthesized and structurally characterized by single‐crystal X‐ray diffraction. Complexes 1 , 3 , 6 , and 7 are molecular dinuclear metal complexes. Complexes 2 , 4 , and 5 exhibit chain‐like structures. Compound 8 shows a novel 3D architecture, in which Zn^II dimers are connected by four NDC^2– anions. In the metal(II) complexes, HIMP exhibits a similar chelating coordination mode. Different π ··· π stacking interactions are observed in the complexes. The emission of HIMP is completely quenched in complexes 1 – 4 due to the strong π ··· π stacking interactions in the structures. Complexes 5 – 8 exhibit different photoluminescence properties. Firstly, we quantitatively investigated the effect of the strong HIMP–HIMP stacking interactions on the emission quenching of HIMP in the metal complexes. It was found that a higher extent of π ··· π stacking interactions in the complexes resulted in a higher extent of the emission quenching of HIMP. The introduction of aromatic conjugated carboxylate groups into metal(II)‐HIMP complexes changed the extent of the strong π ··· π stacking interactions in the structures and thus the photoluminescence properties of the complexes.     

Linear‐dendritic block copolymer hosts for the encapsulation of electro‐optic chromophores via H‐Bonding

Linear‐dendritic block copolymer hosts were synthesized by end‐functionalizing poly(methylmethacrylate) with dendrons that acted as hydrogen‐bonding acceptors for nonlinear optical chromophores. Second harmonic generation experiments indicate that the d₃₃ coefficients and maximum chromophore loading are increased in linear‐dendritic block copolymer hosts over comparable homopolymer hosts. Transmission electron microscopy shows 5–10 nm chromophore domains, confirming the effective spatial dispersion of the chromophores. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5017–5026, 2009     

A Systematic Study of Peripherally Multiple Aromatic Ester‐Functionalized Poly(benzyl ether) Dendrons for the Fabrication of Organogels: Structure–Property Relationships and Thixotropic Property

A new class of peripherally multiple aromatic ester‐functionalized poly(benzyl ether) dendrons and/or dendrimers with different focal point substituents, surface groups, interior structures, as well as different generations have been synthesized and their structure–property relationships with respect to their gelation ability have been investigated systematically. Most of these dendrons are able to gel organic solvents over a wide polarity range. Evident dendritic effects were observed not only in gelation capability but also in thermotropic, morphological, and rheological characterizations. It was disclosed that subtle changes in peripheral ester functionalities and interior dendritic structures affected the gelation behavior of the dendrons significantly. Among all the dendrons studied, the second‐ and third‐generation dendrons G₀G₂‐Me and G₀G₃‐Me with dimethyl isophthalates (DMIP) as peripheral groups exhibited the best capability in gelation, and stable gels were formed in more than 22 aromatic and polar organic solvents. The lowest critical gelation concentration (CGC) reached 2.0 mg mL^?1, indicating that approximately 1.35×10⁴ solvent molecules could be entrapped by one dendritic molecule. Further study on driving forces in gel formation was carried out by using a combination of single‐crystal/powder X‐ray diffraction (XRD) analysis and concentration‐dependent (CD)/temperature‐dependent (TD) ¹H NMR spectroscopy. The results obtained from these experiments revealed that the multiple π–π stacking of extended π‐systems due to the peripheral DMIP rings, cooperatively assisted by non‐conventional hydrogen‐bonding, is the key contributor in the formation of the highly ordered supramolecular and fibrillar network. In addition, these dendritic organogels exhibited unexpected thixotropic‐responsive properties, which make them promising candidates with potential applications in the field of intelligent soft materials.     

Crystal Structures and Proton Conductivities of a MOF and Two POM–MOF Composites Based on CuII Ions and 2,2′‐Bipyridyl‐3,3′‐dicarboxylic Acid

We have succeeded in constructing a metal–organic framework (MOF), [Cu(bpdc)(H₂O)₂]_n (H₂bpdc=2,2′‐bipyridyl‐3,3′‐dicarboxylic acid, 1 ), and two poly‐POM–MOFs (POM=polyoxometalate), {H[Cu(Hbpdc)(H₂O)₂]₂[PM₁₂O₄₀] ? n H₂O}_n (M=Mo for 2 , W for 3 ), by the controllable self‐assembly of H₂bpdc, Keggin‐anions, and Cu²⁺ ions based on electrostatic and coordination interactions. Notably, these three compounds all crystallized in the monoclinic space group P2₁/n, and the Hbpdc^? and bpdc^2? ions have the same coordination mode. Interestingly, in compounds 2 and 3 , Hbpdc^? and the Keggin‐anion are covalently linked to the transition metal copper at the same time as polydentate organic ligand and as polydentate inorganic ligand, respectively. Complexes 2 and 3 represent new and rare examples of introducing the metal N‐heterocyclic multi‐carboxylic acid frameworks into POMs, thereby, opening a pathway for the design and the synthesis of multifunctional hybrid materials based on two building units. The Keggin‐anions being immobilized as part of the metal N‐heterocyclic multi‐carboxylic acid frameworks not only enhance the thermal stability of compounds 2 and 3 , but also introduce functionality inside their structures, thereby, realizing four approaches in the 1D hydrophilic channel used to engender proton conductivity in MOFs for the first time. Complexes 2 and 3 exhibit good proton conductivity (10^?4 to ca. 10^?3 S cm^?1) at 100 °C in the relative humidity range 35 to about 98 %.