Diketopyrrolopyrrole based D-π-A-π-D type small organic molecules as hole transporting materials for perovskite solar cells

Three novel diketopyrrolopyrrole(DPP) based small organic molecules were synthesized as hole transporting materials for perovskite solar cells. The effects of different donors and π bridges on the performance of perovskite solar cells(PSCs) were discussed. The efficiency of TPADPP-1, TPADPP-2, PTZDPP-2 was 5.10%, 9.85% and 8.16% respectively. Compared to TPADPP-2, the voltage of PTZDPP-2 was higher. Because the electron-donating ability of phenothiazine based donor was larger than that of triphenylamine based donor, the HOMO level of PTZDPP-2 was lower than that of TPADPP-2. The results indicated that the diketopyrrolopyrrole based D-π-A-π-D type small organic molecule might be a promising hole transporting material in the perovskite solar cells.

Supramolecular cyclization induced emission enhancement in a pillar[5]arene probe for discrimination of spermine

Early diagnosis and treatment of cancer requires the development of tools that are both sensitive and selective in detecting spermine.In this study,we presented a"supramolecular cyclization-induced emission enhancement"strategy for the sensitive and selective detection of spermine.A new pillar[5]arene probe(P1)demonstrated excellent solution/solid dual-state emission properties,and the addition of certain spermine(Spm)resulted in fluorescence enhancement due to the synergy of multiple weak interactions that restricted the free motion of P1 in the P1⊃Spm complex.This mechanism was further confirmed by time-resolved spectroscopy,DFT calculations,and IGM analysis.With its low limit of detection and high selectivity,P1 is a promising tool for measuring spermine in artificial urine samples.

Unsymmetrical photochromic bithienylethene-bridge tetraphenylethene molecular switches:Synthesis,aggregation-induced emission and information storage

Aggregation-induced emission(AIE) active photochromic molecules have attracted growing attention for their versatile applications.Here we designed and synthesized five newly unsymmetrical photochromic diarylethene(DAE) dyads(BTE1-5) by connecting tetraphenylethene(TPE) and aromatic substituent via bithienylethene(BTE) bridge.The chemical structures of those compounds were identified by ^1H NMR,^(13)C NMR and HRMS.The absorption and emission of these dyads were investigated by UV-vis and fluore scence spectroscopy,respectively.The results showed that all those compounds exhibited typically AIE or aggregation-induced emission enhancement(AIEE) characteristic.Particularly,when an aggregationcaused quenching(ACQ) fluorophore(triphenylamine) was grafted to the molecule,connecting with TPE via BTE-bridge,the ACQ phenomenon was dissipated and converted to an AIE luminophore,and those compounds exhibited photochromism upon irradiation with alternative UV and visible light.The solution or solid of those compounds showed distinctly fluorescence switching "ON" or "OFF" observation upon irradiation with alternative UV and visible light.It is interesting that BTE1 could be applied in recording and rewritable information storage,and the cyclization quantum yields could be affected by substituent significantly.

Photo-induced morphology transition of a multifunctional photochromic bisthienylethene molecule with switchable aggregation-induced emission

A novel multifunctional molecule BTE-CNPH was designed and synthesized by connecting 2-(3′,5′-bis(trifluoromethyl)-biphenyl-4-yl)-2-cyanovinyl group to both side of the bisthienylethene(BTE), which exhibited excellent aggregation-induced emission(AIE) and bistable photochromism. High-contrast(>60) reversible fluorescence switching was achieved in the 1 D nanowires, solid of BTE-CNPH and also in a polymethyl methacrylate(PMMA) film loaded with 1% BTE-CNPH under the alternative irradiation by 365 nm and visible light. Interestingly, the nanowire-like assembly morphology of BTE-CNPH in aqueous tetrahydrofuran(THF) solution of specific concentration was observed to translate into amorphous pieces gradually upon prolonged irradiation by the 365 nm, accompanying with photo-tunable AIE emission.

Complexation Selectivities of Pillar[5]arenes with Primary Ammonium Salts

代替烷基的支柱的 complexation [5 ] 有主要的铵盐的 arenes 被调查。1,4 二度(methoxy ) 支柱[5 ] arene (MeP5 ) 能在 CDCl3 与主要的铵盐形成强壮的建筑群。然而， 1,4 二度(ethoxy ) 支柱[5 ] arene (EtP5 ) 与这些客人，和 1,4 二度(butoxy ) 支柱显示出弱相互作用[5 ] arene (BuP5 ) 根本不能形成如此的建筑群。这些结果显示修改烷基支柱锁住[5 ] arene 玩在 complexation 选择的一个重要角色。

Hexnut[12]arene and its derivatives: Synthesis, host-guest properties, and application as nonporous adaptive crystals

Hexnut[12]arene(HN[12])and its derivatives,a new class of sixfold macrocyclic arenes,were designed and synthesized in reasonable yield by a one-pot reaction at room temperature using dimethoxymethane as a methylene source.HN[12],which bears a large,symmetric,and rigid cavity,was easily functionalized at both the methylene bridges and the hydroquinone units.A water-soluble fluorescent HN[12]was synthesized and used as a host to encapsulate benzyl viologen dichloride in water with a high binding affinity of(3.4±0.2)×10^(6)M^(-1).The nonporous adaptive crystal(NAC)of HN[12]was found to capture not only inorganic molecules(iodine)but also trace amounts of large organic molecules(basic fuchsine)from water,which greatly expands the scope of NACs for adsorption.

Pillararene-based fluorescent sensors for the tracking of organic compounds

Fluorescent chemosensors based on pillararene complexes represent a new, promising branch in sensor technology. Because of CH-π interactions, aliphatic chains are well suited for the columnar cavities of pillararenes and bulky or sheet-like(sub)structures can be arranged on the portals. Thus, pillararenes form versatile receptors and an alteration of the fluorescence behavior upon complexation ensures the function of these chemosensors as the reporter. Although this field of research exists only since a few years, remarkable chemosensors were developed for substances as diverse as medical drugs,biochemicals, herbicides and explosives.

Crystal Structure and Host-Guest Binding Ability of Three Types of Pillar[5]arenes

A systematic research of the structural characterization and the host-guest binding abilities between three types of pillar[5]arenes 3-5(3 for Structure Type I,4 for Structure Type II and 5 for Structure Type III)is carried out by 1H NMR measurements and X-ray study.The results show that the configurations or symmetry of their cavities not only have large difference in these three types of pillar[5]arenes,but also have more or less variations even in the same structure type or the same host locked different guests such as crystals of 3a-3b,4a-4d.On the other hand,the complexation behavior of pillar[5]arenes with 1,4-dibromobutane(DBB)is affected by the different symmetri-cal structure or substituents on the rings.

Special Issue of“Pillararenes”

Organic supramolecular chemistry based on syn-thetic macrocycles has been playing a crucial role in chemistry,biology,materials science,and environ-mental science.As a rapid developing class of syn-thetic macrocycles with intrinsic characteristics and excellent properties first discovered in 2008,pil-lararenes(or pillarenes)have become more and more attractive on account of their unique features and great potentials in fabricating functional materials and devices.The past seven years have witnessed the innovative efforts of Chinese supramolecular chem-ists in developing and revolutionizing pillararene chemistry,and in particular,in seeking the real appli-cations of pillararenes in many research disciplines.