Side-chains Engineering of Conjugated Polymers toward Additive-free Non-fullerene Organic Solar Cells

Side-chain engineering plays a significant role in the design of conjugated materials. In this work, a series of conjugated polymers PBDB-T-R with functionalized groups at the end of side units were developed as electron donor for organic solar cells(OSCs). The donor polymers PBDB-T-I and PBDB-T-OAc with iodine and acetate end groups exhibited similar absorption and energy levels, but showed much improved PCEs in OSCs compared to the polymer PBDB-T-H without substitutions at the end groups. Additionally, we found that PBDB-T-I and PBDB-T-OAc based cells exhibited optimized performance when using chloroform as solution-processed solvent without any additives. These results indicate that these conjugated polymers can act as self-additive to fabricate photoactive layers via solution process in OSCs.     

Micelle or polymersome formation by PCL-PEG-PCL copolymers as drug delivery systems

Polymeric micelles and polymersomes may have great potential as the drug delivery vehicles for solubilization of hydrophobic drugs.     

SNAP-tag fluorogenic probes for wash free protein labeling

In this review, we described the design strategies of SNAP-tag fl uorogenic probes with turn-on fl uorescence responses, which minimized the fl uorescence background and allowed for direct imaging in living cells without wash-out steps. These probes can apply in real-time analysis of protein localization, dynamics, and protein– protein interactions in living cells. Furthermore, the excellent fl uorescent properties made it possible to apply some of the probes in super-resolution fl uorescence imaging.     

Effect of terminal substituents on self‐assembly behavior of porphyrin molecules on Ag(110)

Effect of terminal substituents on self‐assembly behavior of porphyrin molecules has been studied with three derivatives modified with distinctly different substituents, 5,15‐(di‐3,5‐di‐tert‐butylphenyl) porphyrin, 5,15‐(dimesityl) porphyrin, and 5,15‐(di‐4‐ethynylphenyl) porphyrin. Scanning tunneling microscopy and density functional calculations reveal that 5,15‐(di‐3,5‐di‐tert‐butylphenyl) porphyrin, 5,15‐(dimesityl) porphyrin, and 5,15‐(di‐4‐ethynylphenyl) porphyrin spontaneously give different ordered structures on Ag(110) surface both at room temperature and after annealing. It is clear that the tert‐butylphenyl substituent could increase the intermolecular van der Waals interactions to form stable network structure under condition of thermal activation, whereas the mesityl substituent plays an essential role in the formation of rigid chain structure as a result of the CH–π interactions between the mesityl groups of molecule enantiomers. Moreover, the ethynylphenyl substituent could induce metal atoms to coordinate with ethynyl to form organometallic chains. Copyright © 2016 John Wiley & Sons, Ltd.     

A coumarin-based fluorescent and colorimetric chemosensor for rapid detection of fluoride ion

A novel coumarin-based compound 1 featuring thiosemicarbazone as binding unit, was reported as a colorimetric and fluorescent probe for the detection of fluoride anion. The addition of F^? to a solution of probe 1 in tetrahydrofuran resulted in evident naked-eye color change from green-yellow to orange-red under daylight and obvious fluorescence quenching within 3 s. And the detection limit toward F^? was calculated to be as low as 2.16 × 10^?7 mol/L. ¹H NMR titrations proved that the interaction between 1 and fluoride ion: hydrogen bond at low fluoride ion concentration, deprotonation at high fluoride ion concentration. Besides, it exhibited highly sensitivity and selectivity for F^? over other examined ions (Cl^?, Br^?, I^?, AcO^?, NO₃^?, HSO₄^?, H₂PO₄^?) in tetrahydrofuran solution.     

Preparation and characterization of biosurfactant based on hydrophobically modified alginate

Hydrophobic modified alginate (HM-alginate) was synthesized using a low-energy, environment-friendly process in aqueous solution, with sodium alginate and dodecyl glycidyl ether as starting materials. The HM-alginate was characterized using ¹H NMR, and the reaction efficiency was about 40%. The HM-alginate aggregated in solution; the critical micelle concentration (CMC) was determined using surface tension and dynamic light scattering methods. We observed reasonable agreement between the CMC values obtained by the different techniques, and the CMC was 4.0 × 10^?4 g/mL. The zeta-potential of the HM-alginate in aqueous solution was about ?82 mV, which is higher than ?51 mV of the sodium alginate. Rheology measurements showed that the HM-alginate solution exhibits a Newtonian behavior at all shear rates, whereas the apparent viscosity is very low. The solubility of the liposoluble substance Sudan IV increased significantly with HM-alginate concentration. This result is promising for potential applications of HM-alginate as an ecology-safe material to encapsulate lipophilic substances.     

A Cobalt‐Catalyzed Alkene Hydroboration with Pinacolborane

An extremely efficient cobalt catalyst for the hydroboration of both vinylarenes and aliphatic α‐olefins with pinacolborane is described, providing the anti‐Markovnikov products with excellent regio‐ and chemoselectivity, broad functional‐group tolerance, and high turnover numbers (up to 19 800). The alkene hydroboration route is further extended to a two‐step, one‐pot hydroboration and cross‐coupling of alkylboronates with aryl chlorides.     

Switching of the Magnetocaloric Effect of MnII Glycolate by Water Molecules

The transformation of Mn^II glycolates (glc) between the three‐dimensional coordination polymer [Mn(glc)₂]_n ( 1 ) and discrete mononuclear phase [Mn(glc)₂(H₂O)₂] ( 2 ) can be reversibly switched by water molecules, which dramatically change the magnetocaloric effect (MCE) of Mn^II glycolates from the maximum of 6.9 J kg^?1 K^?1 in 1 to 60.3 J kg^?1 K^?1 in 2 . This case example reveals that the effect of magnetic coupling on MCE plays a dominant role over that of other factors such as magnetic density for 3d‐type magnetic refrigerants.     

Efficient synthesis of highly enantiopure β-lactam derivatives from biocatalytic transformations of amides and nitriles

Catalyzed by Rhodococcus erythropolis AJ270, a nitrile hydratase and amidase containing microbial strain, under mild conditions, kinetic resolution of racemic amides provides an efficient and scalable route to highly enantioenriched R-4-carboxymethyl-β-lactams and S-4-carbamoylmethyl-β-lactams despite the substrates contain a stereogenic center that is β-positioned to amide functionality. Synthetic potential of the method was demonstrated by the constructions of novel β-lactam-fused heterocyclic compounds through convenient and practical chemical transformations.