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Chiral cyclic tetraphenylethylenes (TPEs) were synthesized by cyclization with chiral binaphthols. The helical conformation can be immobilized and multi-isomers can be separated resulting from ( Z / E )-isomerism and helical chirality of TPE. The chiral cyclic TPEs can emit deep blue circularly polarized luminescence (CPL) in both solution and film states.

Chiral macrocycles with circularly polarized luminescence (CPL) have attracted increasing attention due to the rigid structure, symmetrical chiral geometry and large luminescence dissymmetry factors (glum). However, most chiral macrocycles are more emissive in solutions but have weakened fluorescence quantum yields (ΦF) in aggregates, limiting their further application. In this paper, chiral macrocycle R/S‐PhTPE was synthesized by combining chiral macrocycle architectonics with Z‐o‐phenyltetraphenylethylene (PhTPE) foldamer. Enhanced solution state emission and characteristic aggregation enhanced emission (AEE) effect can be observed for R/S‐PhTPE due to the folded PhTPE conformation. Macrocycle immobilization and folded conformation endow PhTPE moiety with stable helical conformation. Most importantly, R/S‐PhTPE exhibits opposite CPL signals compared with common chiral TPEs, demonstrating the evident impact of folded conformation. This work reports the first and deep insights into the chiroptical properties of chiral PhTPE foldamers, and will provide a new strategy to tune ΦF and CPL signals of AIE active chiral macrocycles. [ABSTRACT FROM AUTHOR]

• Three pairs of chiral binaphthyl based macrocyclic tetraphenylethylenes (TPEs) with flexible macrocycle backbones and different linkage lengths were designed and synthesized. • The homochiral helical orientations of TPEs in the crystal structures demonstrate the successful chirality transfer from chiral binaphthyl to TPE via the soft macrocycle backbone. • Obvious aggregation-induced emission (AIE) and CPL properties can be detected owing to the chiral macrocyclic architectures. • The chiral macrocycle with the longest linkage length can produce the largest aggregation-induced circularly polarized luminescence (AI-CPL) signals in films with luminescence dissymmetry factor (g lum) up to 1.9 × 10−3. Developing chiral macrocycles with intense circularly polarized luminescence (CPL) has received considerable interest. The chirality transfer in the chiral macrocycles with separated chiral sources and luminophores is crucial but rarely explored. In this paper, we designed and synthesized three pairs of chiral binaphthyl based macrocyclic tetraphenylethylenes (TPEs) with flexible macrocycle backbones and different linkage lengths. The homochiral helical orientations of TPEs in the crystal structures demonstrate the successful chirality transfer from chiral binaphthyl to TPE via the soft macrocycle backbone. Obvious aggregation-induced emission (AIE) and CPL properties can be detected owing to the chiral macrocyclic architectures. Most importantly, the chiral macrocycle with the longest linkage length can produce the largest aggregation-induced circularly polarized luminescence (AI-CPL) signals in films with luminescence dissymmetry factor (g lum) up to 1.9 × 10−3. [Display omitted] [ABSTRACT FROM AUTHOR]

We herein present MOF-808-Tb nanospheres synthesized by a microwave-assisted approach with post-synthetic modification. The hybrid material exhibits an outstanding lanthanide-based luminescence sensing performance toward acetone vapor and Fe3+ cations in aqueous solution. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we designed a kind of aggregation‐induced emission (AIE) chiral fluorescence emitters (R/S‐BINOL‐CN enantiomers) in the aggregate state. Chiral emissive nematic liquid crystals (N*‐LCs) prepared by doping this kind of AIE‐active R/S‐BINOL‐CN enantiomers into a common achiral nematic liquid crystal (N‐LC, E7) can self‐assemble as the regularly planar Grandjean texture leading to high luminescence dissymmetry factor (glum) of aggregation‐induced circularly polarized luminescence (AI‐CPL) signal up to 0.41, which can be attributed to dipolar interactions from polar cyano groups and π–π interactions between binaphthyl moiety of the dopant R/S‐BINOL‐CN and biphenyl group of the host molecules (E7). [ABSTRACT FROM AUTHOR]

ABSTRACT: Two kinds of chiral 1,1′‐binaphthol (BINOL)‐based polymer enantiomers were designed and synthesized by the polymerization of 5,5′‐((2,2′‐bis (octyloxy)‐[1,1′‐binaphthalene]‐3,3′‐diyl)bis(ethyne‐2,1‐diyl))bis(2‐hydroxybenzaldehyde) (M1) with alkyl diamine (M2) via nucleophilic addition–elimination reaction. The resulting chiral polymers can exhibit mirror image cotton effects either in the absence or in the presence of Zn2+ ion. Almost no fluorescence or circularly polarized luminescence (CPL) emission could be observed for two chiral BINOL‐based polymer enantiomers in the absence of Zn2+. Interestingly, the chiral polymers can show strong fluorescence and CPL response signals upon the addition of Zn2+, which can be attributed to Zn2+‐coordination fluorescence enhancement effect. This work can develop a new strategy on the design of the novel CPL materials via metal‐coordination reaction. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1282–1288 [ABSTRACT FROM AUTHOR]

Two perylene diimide (PDI) enantiomers ( d/l-PDI) incorporating the d/ l-alanine moiety have been designed and synthesized. d/l-PDI in chloroform displays bright-yellow fluorescence that is redshifted to orange-red when the solvent contains a methanol fraction of 99 vol %. No circular dichroism (CD) or circularly polarized luminescence (CPL) signals were observed for d/l-PDI enantiomers in CHCl3. Interestingly, the d/l-PDI enantiomers exhibit clear mirror-image Cotton effects and CPL emission in the aggregate state. The optical anisotropy factor ( glum) is as high as 0.02 at fm=99 %, which can be attributed to self-assembly through intermolecular π-π interactions in the aggregate state. [ABSTRACT FROM AUTHOR]

Four chiral 1,2-diaminocyclohexane (DACH)-based molecules ( R, R/ S, S- 2 and R, R/ S, S- 4) incorporating 1,8-naphthalimide fluorophores exhibit strong circularly polarized luminescence (CPL) emission signals in common organic solvents. Interestingly, the reversed CPL signals can be observed in the aggregated state, which is due to the orderly aggregation. [ABSTRACT FROM AUTHOR]

Two AIE-active chiral BINOL-based O-BODIPY enantiomers (R/S-5) were synthesized and showed mirror-image red-color CPL induced via intramolecular energy transfer. The chiroptical properties of the molecules indicate that the chirality of electronic ground and excited states is stable and independent of aggregation. [ABSTRACT FROM AUTHOR]

One new polymer, [Ag 4 (C 5 O 5 ) 2 (H 2 O) 2 ] n (C 5 O 5 2− = croconate dianion), has been synthesized and characterized by element analysis, IR, Raman, single-crystal X-ray diffraction, PXRD, and luminescent analysis. X-ray structural analysis revealed that the ligand was de-protonized entirely and offered five oxygen donors taking part in the coordination, and the tetranuclear silver(I) ions showed 4 and 5 coordination geometries respectively. From the space perspective, the presence of 1D chains that are connected into 2D layers, which are further connected into 3D network can be found within the crystal structure by Ag O and weak Ag⋯Ag interactions. The thermal decomposition process consists of the loss of corresponding water molecules below 380 °C and follow-up decomposition of the main structure. Under the excitation of 380 nm light, the complex displayed green luminescent emission at room temperature. [ABSTRACT FROM AUTHOR]

Materials capable of circularly polarized luminescence (CPL) have generated intensive interest for their potential applications. However, constructing chiral molecules with tunable CPL signals remains a challenge. In this paper, two pairs of binaphthylamine based chiral donors R / S -2 and R / S -3 were synthesized by Pd-catalyzed C–N coupling and intramolecular oxidative coupling with good yields. Then three pairs of chiral D-A type molecules R / S -4∼6 can be synthesized by introducing two kinds of achiral acceptors. The extention of the chiral binaphthy skeleton endows these chiral compounds with CPL signals ranged from 417 nm to 544 nm in solutions and film states. The g lum can be up to −2.9 × 10−3 for R -2 in solution. The introduction of terephthalonitrile as acceptor endow R / S -4 thermally activated delayed fluorescence (TADF). Furthermore, when benzophenone is chosen as achiral acceptor, the obtained chiral D-A molecules R / S -5 and R / S -6 can exhibit reversed CPL signals compared with their corresponding chiral donors. This work demonstrates the introduction of chiral D-A structure not only alters the wavelength of the CPL signals but also can reverse the CPL sign. [Display omitted] • Chiral binaphthylamine based donors and D-A type molecules were designed rationally and synthesized efficiently. • The extention of the chiral binaphthy skeleton endows these chiral compounds with CPL signals ranged from 417 nm to 544 nm. • The introduction of different achiral acceptors can result in CPL signals with opposite signs. [ABSTRACT FROM AUTHOR]