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Solid-state multiple [2 + 2] cycloaddition reactions of polyenes continue to attract attention as a mediate for the synthesis of polycyclobutane derivatives. The solid and crystalline states of polyenes restrict molecular movements of C＝C bonds and, as a result, contribute to the selective formation of polycyclobutane derivatives through photochemical [2 + 2] cycloaddition reactions. In this review, functionalised polyenes preorganised by suitable templates, such as muconate and 4-pyr-poly-2-ene (ppene) derivatives, are summarised and their multiple [2 + 2] cycloaddition reactions are described, which lead to the generation of polycyclobutane derivatives in the solid state. Single-crystal-to-single-crystal (SCSC) transformations in which the single-crystal character is preserved along the reaction sequence are emphasised, as they provide unambiguous information regarding the structural changes during the reaction. [ABSTRACT FROM AUTHOR]

In this study, a kind of non-precious glass bead catalyst was prepared by a subcritical water treatment method for the depolymerization of poplar lignin. The subcritical water treatment time significantly affected the surface morphology, surface area, and active metal content of glass bead catalysts. Flaky and fibrous morphologies were found on the glass bead surface after it was treated for 60 min and 120 min, respectively. Based on the GC-MS results of monomeric products, the glass beads treated for 60 min had higher catalytic activity as compared to those treated for 120 min. The characterization results of lignin residues suggest that the glass beads are effective to prevent the repolymerization of lignin. Furthermore, the glass bead catalysts can be recycled to catalyze the depolymerization of lignin, and the yield of the monomeric products remains above 12 wt%. [ABSTRACT FROM AUTHOR]

An amine-induced phase transition strategy is developed for converting white phosphorus into red or black phosphorus. Amorphous red phosphorus is prepared through the chemical dissolution of white phosphorus in amines and post-treatment at room temperature. It is demonstrated that the phase transformation mechanism involves an amine-induced nucleophile attack on white phosphorus and the generation of polyphosphorus ions. The amorphous phosphorus exhibits a specific capacity of 955.5 mA h g−1 at 1.5 A g−1 after 1000 cycles, and a capacity retention of 1210.2 mA h g−1 even at 20 A g−1 for Li-ion batteries. This methodology is also applicable to produce red phosphorus micro-spheres and black phosphorus particles by varying the types of organic amines and the reaction temperature. [ABSTRACT FROM AUTHOR]

A dynamic guest-binding study of BODIPY-derivative 3 (3 = 1,3,5,7,8-pentamethyl-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) with two Cp*RhIII-based organometallic cages [Cp*6Rh6(μ-CA)3(tpt)2](OTf)61 (H2CA = chloranilic acid, tpt = 2,4,6-tripyridyl-1,3,5-triazine) and [Cp*6Rh6(μ-DHNA)3(tpt)2](OTf)62 (H2DHNA = 6,11-dihydroxynaphthacene-5,12-dione) have been demonstrated. While guest 3 displays a strong green fluorescence emission, the host–guest complexes 3⊂1 and 3⊂2 exhibit almost no emission. However, fluorescence emission can be again ‘turned on’ by adding coronene (4) or pyrene (5) into the solution of 3⊂1 and 3⊂2. Guests 4 and 5 show stronger binding affinities toward the organometallic cages 1 and 2 due to the strong electrostatic interactions between the electron-rich guest and electron-deficient tpt resulting in the displacement of 3 by 4 or 5, which eventually helps the fluorescence enhancement. Further guest-binding studies using a Job's plot experiment illustrate the formation of discrete 1 : 1 host–guest complexes which are also supported by 1H NMR spectroscopy and ESI mass spectrometry. The anion-exchange study with sodium chloride reveals that the chloride ion can effectively disassemble the host frameworks of 1 and 2 releasing the fluorescent guest 3 which can be again encapsulated into the cavity of reassembled cages promoted by the addition of silver triflate. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed intramolecular hydrocarbonation of unactivated alkenes was achieved, in which toluene is used as a hydrogen donor for the first time. The radical transfer hydrogenation is designed and realized based on the Bond Dissociation Energy (BDE) value. A toluene derivative, which is cheap, readily available and easy to handle, serves as a new hydrogen donor in radical involved reactions, providing a novel and promising perspective for future reductive reactions. [ABSTRACT FROM AUTHOR]

A hydrogen-bonded organic framework (HOF) was constructed by avoiding potential π–π stacking of building blocks with robust and non-coplanar triptycene-based modules. The tailored-fitting interactions were demonstrated by the adsorption of fullerene with a concentration enrichment of ∼420 times in the pores. [ABSTRACT FROM AUTHOR]

We report a magnetically transportable microlaser with cholesteric liquid crystal (CLC) core–shell structure, operating in band-edge mode. The dye doped CLC shells as a water-in-oil-in-water (W/O/W) double emulsion were fabricated by microfluidics. Water-dispersible Fe3O4 magnetic nanoparticles were incorporated in the inner aqueous phase by taking advantage of the immiscibility with the middle CLC oil phase. The influence of temperature and shell thickness on laser properties was discussed in detail. The non-invasive manipulation of microlasers was realized under a magnetic field. The dependence of velocity on the viscosity of the carrying fluid and size of the core–shell structure was theoretically analyzed and experimentally investigated using a prototype electromagnetic platform. We also discussed the design principles for this type of DDCLC core–shell structure. Such magnetically transportable microlasers offer promise in in-channel illumination applications requiring active control inside micro-channels. [ABSTRACT FROM AUTHOR]