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X‐ray induced photodynamic therapy (X‐PDT) circumvents the poor penetration depth of conventional PDT with minimal radio‐resistance generation. However, conventional X‐PDT typically requires inorganic scintillators as energy transducers to excite neighboring photosensitizers (PSs) to generate reactive oxygen species (ROS). Herein, a pure organic aggregation‐induced emission (AIE) nanoscintillator (TBDCR NPs) that can massively generate both type I and type II ROS under direct X‐ray irradiation is reported for hypoxia‐tolerant X‐PDT. Heteroatoms are introduced to enhance X‐ray harvesting and ROS generation ability, and AIE‐active TBDCR exhibits aggregation‐enhanced ROS especially less oxygen‐dependent hydroxyl radical (HO•−, type I) generation ability. TBDCR NPs with a distinctive PEG crystalline shell to provide a rigid intraparticle microenvironment show further enhanced ROS generation. Intriguingly, TBDCR NPs show bright near‐infrared fluorescence and massive singlet oxygen and HO•− generation under direct X‐ray irradiation, which demonstrate excellent antitumor X‐PDT performance both in vitro and in vivo. To the best of knowledge, this is the first pure organic PS capable of generating both 1O2 and radicals (HO•−) in response to direct X‐ray irradiation, which shall provide new insights for designing organic scintillators with excellent X‐ray harvesting and predominant free radical generation for efficient X‐PDT. [ABSTRACT FROM AUTHOR]

Luminescent metal–organic frameworks (MOFs) are appealing for the design of smart responsive materials, whereas aggregation‐induced emission (AIE) fluorophores with twisted molecular rotor structure provide exciting opportunities to construct MOFs with new topology and responsiveness. Herein, it is reported that elongating AIE rotor ligands can render the newly formed AIE MOF (ZnETTB) (ETTB = 4',4''',4''''',4'''''''‐(ethene‐1,1,2,2‐tetrayl)tetrakis(([1,1'‐biphenyl]‐3,5‐dicarboxylic acid))) with more elasticity, more control for intramolecular motion, and specific amide‐sensing capability. ZnETTB shows specific host–guest interaction with amide, where N,N‐diethylformamide (DEF), as an example, is anchored through CH···O and CH···π bonds with Zn cluster and ETTB8− ligand, respectively. DEF anchoring reduces both the distortion level and the intramolecular motions of ETTB8− ligand to lead a blueshifted and intensified emission for DEF ∈ ZnETTB. Moreover, amide anchoring also affords the DEF ∈ ZnETTB with the excellent thermofluorochromic behavior, and further increases the piezofluorochromic sensitivity at low‐pressure ranges on the basis of its elastic framework. This work is one of the rare examples of amide‐responsive smart materials, which shall shed new lights on design of smart MOFs with twisted AIE rotors for further sensing and detection applications. [ABSTRACT FROM AUTHOR]

Smart luminescent metal–organic frameworks (MOFs) demonstrate promising performance in the detection of toxic gases. The incorporation of twisted or rotary organic ligands with aggregation‐induced emission (AIE) characteristics can provide further opportunities in designing such smart MOFs with new topologies and stimuli‐responsive behaviors. Herein, novel AIE MOFs are reported with reversible luminescence or a magnetic switch for HCl vapor detection. The twisted conformation of tetrakis(4‐carboxyphenyl)ethylene (TCPE) ligand leads to the unique [M+–L–M−–L–M]∞ (M = metal clusters, L = ligand) configuration for ZnMOF and CoMOF. Different from conventional MOFs with [M–L]∞ topology, ZnMOF and CoMOF exhibit a blue‐to‐yellow greenish fluorescence transition and a ferrimagnetic‐to‐antiferromagnetic switch behavior, respectively, upon recognition of HCl vapor. The adsorbed HCl molecules rather than coordinated ones are determined to be the main reason, and such luminescence and magnetic switch can be induced in a reversible manner via HCl vapor adsorption/desorption processes with high reliability. This work of AIE MOFs with twisted and rotary ligands shall pave new avenue in design of smart MOFs with new topologies and stimuli‐responsive behavior for real‐time sensing and detection applications. [ABSTRACT FROM AUTHOR]

The design and synthesis of clusters possessing the same number of cores but different connection methods and properties have always been difficult. Herein, we used 2‐pyridinaldehyde, 1,3‐diamino‐2‐propanol, and Dy (ClO4)3·6H2O at room temperature (RT) to obtain the cluster [Dy4(L1)4(μ2‐OH)4]·4ClO4− (1, HL1 = 2‐pyridinecarboxaldehyde‐1,3‐diamino‐2‐propanol) with square Dy4O8 cluster cores. Cluster 1 consisted of four Schiff base ligands (L1)−, four Dy(III) ions, four bridged (μ2‐OH)−, and four free ClO4−. The ligand HL1 was formed by in situ Schiff base reaction with 2‐pyridinecarbaldehyde and 1,3‐diamino‐2‐propanol in the presence of Dy(III) ions. 2‐Aldehyde‐8‐hydroxyquinoline, 1,3‐diamino‐2‐propanol, and Dy (NO3)3·6H2O reacted at RT to yield a tetranuclear Dy(III) cluster [Dy4(L2)2(μ3‐OH)2(NO3)4(EtOH)2]·2CH3CN (2, H3L2 = 2‐aldehyde‐8‐hydroxyquinoline‐1,3‐diamino‐2‐propanol) with butterfly‐shaped Dy4O6 cluster core. Cluster 2 consisted of two ligands (L2)3−, four Dy(III) ions, two bridged μ3‐OH, two end‐group‐coordinated ethanol molecules, and four bidentate‐chelated NO3−. The in situ reaction of 2‐aldehyde‐8‐hydroxyquinoline and 1,3‐diamino‐2‐propanol under Dy(III) ion‐assisted catalytic conditions provided the ligand H3L2. It is worth noting that the magnetic test showed that 1 is a typical single‐molecule magnet (SMM), whereas 2 only showed a significant frequency dependence behavior. We considered Orbach and Raman processes (τ−1 = τ0−1 exp(−Ueff/kBT) + CTn) to fit 1 and 2 in the high‐temperature range and obtained Ueff = 7.01 and 5.43 K and τ0 = 1.18 × 10−4 and 4.14 × 10−5 s, respectively. [ABSTRACT FROM AUTHOR]

A dinuclear Dy (III) complex [Dy2(L1)2(NO3)4]·2CH3CN (1) (HL1 = 1,3‐bis{[(E)‐pyridin‐2‐ylmethylene]amino}propan‐2‐ol) was obtained via the reaction of 1,3‐diamino‐2‐propanol, 2‐pyridyaldehyde and Dy (NO3)3·6H2O at room temperature. In the structure of complex 1, two Dy (III) ions are in the N4O6 coordination environment provided by NO3− and (L1)−, and both of these ions are in the sphenocorona configuration. [Dy2(L2)2(NO3)4] (2) [HL2 = 2‐(pyridin‐2‐yl)hexahydropyrimidin‐5‐ol] was obtained using the same reaction material only when the reaction temperature was changed to 60°C. Structural analysis of complex 2 showed that the two Dy (III) ions with the same coordination configuration are in the N3O6 coordination environment provided by NO3− and (L2)− and are in the distorted spherical‐capped square antiprism. Surprisingly, HL2 with the parent of bipyridine was synthesized by the Schiff base reaction of 1,3‐diamino‐2‐propanol with 2‐pyridoxaldehyde followed by the ring‐closing reaction catalyzed by Dy (III) ions. Magnetic measurements of the Dy (III) complexes revealed no obvious frequency‐dependent behavior of complex 1. In contrast, complex 2 showed an obvious frequency dependence (Ueff = 0.49 K and τ0 = 6.62 × 10−4 s) under the condition of zero field and a weak double relaxation behavior (Ueff = 9.25 K and τ0 = 9.70 × 10−4 s) at 1500 Oe. [ABSTRACT FROM AUTHOR]

Metal nanoclusters have a certain rigidity due to their specific coordination patterns and shapes; thus, they face extreme difficulty in folding into a specific direction to form a double‐helix structure and in further interconnecting to form metal–helix frameworks (MHFs). To date, no MHFs have been produced by the formation of heterometallic clusters. Selecting the appropriate "bonding molecules" to bond metal nanoclusters in a specific multiple direction is one of the most effective strategies for designing synthetic MHFs. In this study, we realized for the first time the control of different orientations of μ3‐NO3− to join heterometallic clusters (Cu10Dy2) and subsequently form a left‐handed double helix chain, which further joins to form MHFs. In the structure of the MHFs, four different directions of bridging μ3‐NO3− exist, three of which are involved in the linkage of the double‐helix chain. Each μ3‐NO3− is connected to three adjacent Cu10Dy2. Herein, we extend a new method for designing synthetic double‐helix structures and MHFs, thereby further laying the foundation for the development of similar DNA double‐helix structures and nucleic acid secondary structures in vitro. [ABSTRACT FROM AUTHOR]

A new free carbon radical was obtained in a microwave‐assisted solvothermal reaction of the primary amine (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)methanamine with FeCl3⋅6 H2O in methanol at 140 °C. Through a combination of crystallography and electrospray ionization mass spectrometry, the reaction process was studied. The longest domino reaction includes 14 steps and forms up to 12 new covalent bonds (9 C−N and 3 C−C bonds) and 3 five‐membered heterocycles. For the first time, the homolytic cleavage of a C−O bond was used to synthesize a triarylmethyl radical. A free carbon radical was obtained in a domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. In this process, which was studied by crystallography and ESI mass spectrometry, the longest domino reaction features 14 steps, and methanol is sequentially activated; in addition, the homolytic cleavage of a C−O bond is proposed. [ABSTRACT FROM AUTHOR]

Domino Reactions. In their Communication on page 3748 ff., M.‐H. Zeng et al. describe the synthesis of a free carbon radical through the domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. [ABSTRACT FROM AUTHOR]