A Dicyanomethylene-4H-Pyran Based NIR Ratiometric Fluorescent Probe for Diazane and its Bioimaging.

A near-infrared ICT-based fluorescent probe LX was successfully obtained. LX which detection limit is low as 22.2 nm shows excellent selectivity and high sensitivity to diazane. LX can selectively detected diazane from other species over a wide pH (3-10) range. A obvious color change of solution from yellow to orange can be found, allowing the naked eye to detect. The sensing mechanism was reasonably detected by ESI-MS and DFT calculations. In addition, LX succeed in the visualization of diazane in living cells and the detection of diazane in water samples.

A Fluorescein-Based Colorimetric and Fluorescent Probe for Hydrazine and its Bioimaging in Live Cells.

A turn-on fluorescent probe (FN) for detection of hydrazine has been developed. Probe FN exhibited high selectivity and excellent sensitivity towards hydrazine with a detection limit as low as 4.6 × 10-10 M. Probe FN selectively reacts with hydrazine (N2H4) in a physiological environment, leading to an off-on fluorescence response along with the color change from colorless to yellow, allowing colorimetric detection of hydrazine by the naked eye. Furthermore, probe FN was successfully applied for visualizing hydrazine in living cells.

A Rhodamine-Benzimidazole Based Chemosensor for Fe(3+) and its Application in Living Cells.

A rhodamine-benzimidazole based chemosensor was designed and prepared for Fe(3+) via opening of the spiro-ring to give fluorescent and colored species. L exhibited high selectivity and excellent sensitivity in both absorbance and fluorescence detection of Fe(3+) in aqueous solution with comparatively wide pH range (5.8-7.4). The detection limit of this newly developed probe was shown to be up to 2.74 µM. The reversibility establishes the potential of both probes as chemosensors for Fe(3+) detection. Fluorescence imaging experiments of Fe(3+) in living MGC803 cells demonstrated its value of practical applications in biological systems.

Two new reversible naphthalimide-based fluorescent chemosensors for Hg(2.).

Naphthalimide-based fluorescent probes 1 and 2 were synthesized, and were designed to form probe-Hg complexes through Hg(2+) ions coordinated to the amide group and imidazole group. They showed high sensitivity and were selective 'naked-eye' chemosensors for Hg(2+) in phosphate buffer. The fluorescence of compounds 1 and 2 could be quenched up to 90% by the addition of Hg(2+) . Reversible probes can detect Hg(2+) ions over a wide pH range (7.0-10.0). Copyright © 2015 John Wiley & Sons, Ltd.

Structures and Luminescent Properties of Two 2D Coordination Polymers Containing Tb(III) or Dy(III) Ions.

Two 2D rare earth terbium and dysprosium coordination polymers with 2,4-pyridinedicarboxylate and oxalate anions have been synthesized by hydrothermal method, the formula is {[RE(pda)(ox)0.5(H2O)4]·2H2O}n (RE = Tb (1) and Dy (2); H2pda = 2,4-pyridinedicarboxylic acid; ox = oxalate anion). The two complexes are isomorphic and crystallized in monoclinic system, P21/c space group. Each pda anion connects two rare earth ions with 2- carboxyl group and the nitrogen atom but the 4- carboxyl group does not coordinate with rare earth ions. Each ox anion connects two rare earth ions by µ 2-bridge way. Both the complexes exhibit intense characteristic luminescence of Tb(III) or Dy(III) ion with excitation of UV-rays.

Preparation, structure and near-infrared luminescent property of Yb(III) complex with 2,4,6-pyridinetricarboxylic acid.

A rare earth ytterbium complex with 2,4,6-pyridinetricarboxylic acid (H(3)pta) has been synthesized by hydrothermal method, the formula is {[Yb(2)(pta)(2)(H(2)O)(3)]·H(2)O}(n). The complex crystallized in monoclinic system, P2(1)/c space group with lattice parameters a = 11.6556(19)Å, b = 7.8364(12), c = 22.020(4), α = γ = 90º, ß = 92.120(3), Z = 4, GOF = 1.026, R1 = 0.0334, wR2 = 0.0660. The pta anions connect four rare earth Yb(III) ions with two different coordination modes. The complex exhibit intense characteristic near-infrared luminescence of Yb(III) ions at 990 nm with excitation of UV-rays.

1-(4-tert-Butyl-benz-yl)pyrimidine-2,4(1H,3H)-dione.

The asymmetric unit of the title compound, C(15)H(18)N(2)O(2), contains two independent mol-ecules with essentially identical geometries and conformations. The dihedral angles between the benzene and pyrimidine rings in the two mol-ecules are 89.96 (11) and 73.91 (11)°. The six methyl groups are disordered over two sets of sites, with site occupancies of 0.545 (4):0.455 (4) and 0.542 (7):0.458 (7) in the two mol-ecules. The crystal structure is stabilized by N-H⋯O hydrogen bonds.

6-Benz-yloxy-2-phenyl-pyridazin-3(2H)-one.

In the title compound, C(17)H(14)N(2)O(2), the central pyridazine ring forms dihedral angles of 47.29 (5) and 88.54 (5)° with the benzene rings, while the dihedral angle between the benzene rings is 62.68 (6)°. In the crystal, molecules are linked by two weak C-H⋯O hydrogen bonds and three weak C-H⋯π inter-actions.

Synthesis and properties of a novel decacyclic S,N-heteroacene.

S,N-Heteroacene materials with fused multicyclic heteroaromatics have become increasingly attractive for organic optoelectronic device applications. In this work, the Cadogan ring-closure reaction between the benzene moiety of thieno[3,2-b]indole and 5,6-dinitrobenzo[c][1,2,5]thiadiazole was employed to prepare the novel decacyclic S,N-heteroacene 15,16-dibutyl-14,17-didodecyldithieno[2'',3'':2',3']indolo[6',7':4,5]pyrrolo[3,2-e:2',3'-g][2,1,3]benzothiadiazole (TIP), C58H76N6S3. The conjugated backbone of TIP is extended in comparison with its octacyclic analogue as the central unit within Y6-type molecular acceptors, a family of overwhelming electron acceptors in polymer solar-cell research. The single-crystal X-ray diffraction (SC-XRD) characterization indicated the existence of π-π and C(sp2)-H...π interactions among TIP molecules. The electrochemical and optical properties of TIP were also characterized. As a novel S,N-heteroacene building block, TIP is anticipated to be of potential use in the construction of promising electronic materials.

1,3-Bis(4-tert-butyl-benz-yl)pyrimidine-2,4(1H,3H)-dione.

In the crystal structure of the title mol-ecule, C(26)H(32)N(2)O(2), the six methyl groups are disordered over two positions, with site-occupancy ratios of 0.665 (8):0.335 (8) and 0.639 (8):0.361 (8). The central pyrimidine ring is almost planar with an r.m.s. deviation of 0.009 Å. The dihedral angles formed by the two benzene rings with the pyrimidine ring are 70.70 (8) and 88.02 (9)°. The dihedral angle between two benzene rings is 46.67 (10)°.

Ethyl 6-(4-fluoro-phen-yl)-4-hy-droxy-2-oxo-4-trifluoro-meth-yl-1,3-diazinane-5-carboxyl-ate monohydrate.

The asymmetric unit of the title compound, C(14)H(14)F(4)N(2)O(4)·H(2)O, contains two crystallographically independent organic mol-ecules and two water mol-ecules. The two 1,3-diazinane rings adopt a half-chair conformation and the dihedral angles between their mean planes and those of the benzene rings are 75.65 (4)° and 49.41 (3)° in the two mol-ecules. The crystal structure is stabilized by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds.

Positional isomeric effect of monobrominated ending groups within small molecule acceptors on photovoltaic performance.

As an ending acceptor unit (A) within acceptor-donor-acceptor (A-D-A)-type small molecule acceptors (SMAs), monobrominated 1,1-dicyanomethylene-3-indanone (IC-Br) plays a critical role on developing high-performance SMAs and polymer acceptors from polymerizing SMAs. IC-Br is usually a mixture (IC-Br-m) consisting of positional isomeric IC-Br-γ and IC-Br-δ (bromine substituted on the γ and δ positions, respectively). The positional isomeric effect of these monobrominated ending groups has been witnessed to take an important role on regulating the photovoltaic performance. Fully investigating this isomeric effect of monobromination would be of great value for SMAs and even polymer acceptors. In this study, benefitting from the separation of IC-Br-γ and IC-Br-δ from IC-Br-m with high yields, bis(thieno[3,2-b]cyclopenta)benzo[1,2-b:4,5-b']diselenophene (BDSeT) was chosen as the D unit and combined with IC-Br-γ, IC-Br-δ and IC-Br-m as A units, respectively. Three A-D-A type SMAs (BDSeTICBr-γ, BDSeTICBr-δ and BDSeTICBr-m) have thus been obtained. When blended with the representative donor polymer of PBDB-T-2Cl to construct bulk heterojunction (BHJ) polymer solar cells (PSCs), BDSeTICBr-γ, BDSeTICBr-δ and BDSeTICBr-m devices offered power conversion efficiencies (PCEs) of 9.42, 10.63, and 11.54% respectively. The result indicated the superior photovoltaic performance of the isomer mixture over the pure isomers, which was contrary to the reported ones that the pure isomers of SMAs used to give a better performance. The superior performance of the BDSeTICBr-m devices was mainly reflected in the improved carrier generation and transport as well as the carrier recombination suppression. In the three PBDB-T-2Cl:SMA BHJ films, a comparable intermixing phase and acceptor domain sizes were observed. Compared with BDSeTICBr-γ and BDSeTICBr-δ, BDSeTICBr-m showed a preferential face-on orientated packing with the closest π-π stacking in its BHJ film, probably accounting for its higher photovoltaic performance than those of the pure isomers. This study provides an alternative sight to develop efficient SMAs with suitably monobrominated IC ending groups for the strategy of polymerizing SMAs.

1-Benzoyl-4-(2-nitro-phen-yl)semicarbazide.

The title compound, C(14)H(12)N(4)O(4), was prepared by the reaction of 2-nitro-phenyl isocyanate with benzoyl-hydrazine. The dihedral angle between the rings is 71.49 (6)) Å. The mol-ecular conformation is stabilized by an intra-molecular N-H⋯O hydrogen bond, generating an S(6) ring. The crystal packing shows N-H⋯O hydrogen bonds.

2-Amino-4,6-dimethyl-pyrimidin-1-ium 1-oxo-2,6,7-trioxa-1λ-phosphabicyclo-[2.2.2]octane-4-carboxyl-ate.

In the title compound, C(6)H(10)N(3) (+)·C(5)H(6)O(6)P(-), the cation and anion are linked by pairs of N-H⋯O hydrogen bonds. There are additional inter-molecular N-H⋯N hydrogen bonds, which generate centrosymmetric tetramers of two cations and two anions.

Ethyl 6-[4-(dimethyl-amino)phen-yl]-4-hydr-oxy-2-oxo-4-(trifluoro-methyl)-hexa-hydro-pyrimidine-5-carboxyl-ate.

The title compound, C(16)H(20)F(3)N(3)O(4), was prepared by reaction of 4-(dimethyl-amino)benzaldehyde, ethyl 4,4,4-trifluoro-3-oxo-butanoate and urea. In the title mol-ecule, the pyrimidine ring adopts a half-chair conformation and there is an intra-molecular hydrogen bond (O-H⋯O). The crystal structure is stabilized by two types inter-molecular hydrogen bonds (N-H⋯O and N-H⋯N).

rac-Ethyl 4-hy-droxy-6-(2-hy-droxy-phen-yl)-2-oxo-4-(trifluoro-methyl)per-hydro-pyrimidine-5-carboxyl-ate.

In the title compound, C(14)H(15)F(3)N(2)O(5), prepared by reaction of 2-hy-droxy-benzaldehyde, ethyl 4,4,4-trifluoro-3-oxobutano-ate and urea, the tetra-pyrimidine ring adopts a half-chair conformation. The crystal structure is stabilized by five inter-molecular hydrogen bonds, three O-H⋯O and two N-H⋯O, giving cyclic dimers (through three hydrogen bonds) which are further extended into a two-dimensional network.

6-(Trifluoro-meth-yl)pyrimidine-2,4(1H,3H)-dione monohydrate.

The title compound, C(5)H(3)F(3)N(2)O(2)·H(2)O, was prepared by the reaction of ethyl 4,4,4-trifluoro-3-oxobutano-ate with urea. In the crystal, the 6-(trifluoro-meth-yl)pyrimidine-2,4(1H,3H)-dione and water mol-ecules are linked by N-H⋯O and O-H⋯O hydrogen bonds. A ring dimer structure is formed by additional inter-molecular N-H⋯O hydrogen bonds.

1,3-Bis(4-meth-oxy-benz-yl)-6-methyl-pyrimidine-2,4(1H,3H)-dione.

The title compound, C(21)H(22)N(2)O(4), was prepared by reaction of 6-methyl-pyrimidine-2,4(1H,3H)-dione and 1-chloro-methyl-4-meth-oxy-benzene. In the title mol-ecule, the central pyrimidine ring forms dihedral angles of 62.16 (4) and 69.77 (3)° with the two benzene rings. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into chains.

6-Hy-droxy-4-(pyridin-3-yl)-5-(2-thienyl-carbon-yl)-6-trifluoro-meth-yl-3,4,5,6-tetra-hydro-pyrimidin-2(1H)-one.

In the title compound, C(15)H(12)F(3)N(3)O(3)S, the pyrimidine ring adopts a half-chair conformation with the mean plane formed by the ring atoms excluding the C atom bonded to thio-phene-2-carbonyl group lying nearly perpendicular to the pyridine and thio-phene rings, making dihedral angles of 84.91 (4) and 87.40 (5)°, respectively. The dihedral angle between the pyridine and thio-phene rings is 54.44 (5)°. The crystal structure is stabilized by inter-molecular O-H⋯O and N-H⋯N hydrogen bonds and weak C-H⋯O inter-actions further consolidate the structure.

Bis(thieno[3,2-b]thieno)cyclopentafluorene-Based Acceptor with Efficient and Comparable Photovoltaic Performance under Various Processing Conditions.

The morphology of a bulk heterojunction (BHJ) blend within a polymer solar cell (PSC) device plays a crucial role in its performance. The ideal morphology is generally achieved through molecular engineering and optimization under film processing conditions. Under different processing conditions, the deviation of the resulted morphology characteristics from the ideal one leads to the dispersion of device performance. For a specific donor/acceptor BHJ blend, it is of great challenge to maintain an efficient and comparable photovoltaic performance under various processing conditions. The solution to this challenge would be of great value in offering more choices for a suitable processing technology in practical applications. Based on the acceptor BTTFIC with the core of bis(thieno[3,2-b]thieno)cyclopentafluorene (BTTF) in our previous work, we chemically modified BTTFIC by fluorination of the end groups of 1,1-dicyanomethylene-3-indanones (IC) and the switching part of octyls in BTTF with 4-hexylphenyls to offer a novel acceptor (BTTFIC4F-Ar). The inverted PBDB-T-2Cl:BTTFIC4F-Ar blend device provided an average power conversion efficiency (PCE) of 10.61, 11.08, and 11.55% when processed under solvent annealing (SA), thermal annealing (TA), and additive treatment with 1,8-diodooctane (DIO), respectively. Different from the reported discrete performance under various processing conditions for a specific donor/acceptor BHJ blend, a low mean absolute performance deviation of 3% was attained. This slight enhancement trend was unexceptionally reflected on charge generation, transportation, and recombination within the blend films from SA, TA, and DIO conditions. A slightly improved ordering of BTTFIC4F-Ar within the DIO blend was observed. Meanwhile, very similar molecular packings as well as a close amorphous domain size of the mixture of PBDB-T-2Cl and BTTFIC4F-Ar within the three blends were observed. These morphological characteristics are in good agreement with the photoelectrical conversion performance of the blends under the three processing conditions. Furthermore, similar attenuation behaviors in performance were also observed. This investigation may provide new guidance on the molecular engineering of nonfullerene acceptors to achieve an efficient BHJ blend with more options for a suitable and cost-effective processing method in practical applications.