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Molecular iodine contributes significantly to organic transformations in synthetic organic chemistry. It works effectively due to its mild Lewis acidic character, ability as an oxidizing agent, good moisture stability, and easy availability. It is non-toxic, cost-effective, non-metallic, environmentally benign, and has operational simplicity making it more popular for organic synthesis. In addition, many organic reactions show excellent stereo- and regio-selectivities within a short reaction time in common organic solvents. Previously, we reported the organic transformations catalyzed by molecular iodine up to 2012. In the present review article, we wish to highlight the significant and stringent achievements in molecular iodine catalyzed/promoted reactions from 2013 and onwards for researchers of chemistry, primarily during the last five years. [ABSTRACT FROM AUTHOR]

A new low band gap copolymer containing dialkylfluorene and 4,7-dithienyl-2,1,3-benzothiadiazole (TBT), poly(fluorenevinylene-alt-4,7-dithienyl-2,1,3-benzothiadiazole) (PF-TBT) was synthesized by Heck cross-coupling polymerization. The copolymer is soluble in common organic solvents such as chloroform, tetrahydrofuran and chlorobenzene. The TGA result indicated that the copolymer possesses good thermal stability. The absorption, electrochemical and photovoltaic properties of PF-TBT were investigated and compared with those of poly(fluorenevinylene-alt-4,7-diphenyl-2,1,3-benzothiadiazole) (PF-DBT) whose structure is similar to PF-TBT. The copolymer exhibited a broad absorption band with an absorption edge close to 700 nm and an optical band gap of 1.82 eV. Cyclic voltammetry studies indicated that the relatively low HOMO energy level assured a higher open circuit voltage (Voc) when PF-TBT is used as the donor material in a photovoltaic cell. The bulk heterojunction (BHJ) solar cell using PF-TBT as the donor and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) as the acceptor with the structure of ITO/PEDOT : PSS/copolymer : PCBM/LiF/Al, exhibited a Vocof 0.86 V, short-circuit current density (Jsc) of 3.97 mA cm−2, fill factor (FF) of 0.35, and a power conversion efficiency (PCE) of 1.18% under one sun of AM 1.5 solar simulator illumination (100 mW cm−2). [ABSTRACT FROM AUTHOR]

The synthesis and characterization of a series of monothiophenes and terthiophenes bearing amino acids are reported. The reaction of a thiophene, substituted in position 3 by either a carboxylic acid or an acetic acid moiety, with an alanine methyl ester in the presence of hydroxybenzotriazole (HOBt) and N,N′-dicyclohexylcarbodiimide (DCC) affords several mono/terthiophene-alanine methyl esters. The latter were deprotected to form the corresponding carboxylic acids. Terthiophenes have been prepared in good yields viaa Stille cross coupling reaction, using a dibromothiophene–alanine methyl ester and tri-butyl stannyl thiophene. The newly prepared monomers are very stable in air and in the presence of organic solvents. The optical and electrochemical properties of the monomers and their corresponding polymers were also examined using cyclic voltammetry and indium tin oxide (ITO) electrodes. [ABSTRACT FROM AUTHOR]

Styrenic dendrons functionalized with ferrocenyl and chloromethylsilyl termini were synthesized and polymerized by the AIBN-initiated radical polymerization procedure yielding a ferrocenyl dendronized polymer and a chloromethylsilyl dendronized polymer, respectively. The latter polymer was functionalized with ferrocenyl groups using “click” chemistry. The ferrocenyl dendronized polymers are soluble in common organic solvents such as tetrahydrofuran, dichloromethane, and chloroform. They show a reversible ferrocenyl wave in cyclic voltammetry (CV) and form derivatized Pt electrodes. Their sizes and shapes were examined by size exclusion chromatography (SEC), atomic force microscopy (AFM), dynamic light scattering (DLS) and DOSY 1H NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Four new diacid amides of dicholesteryl l-phenylalaninate were designed and prepared. The compounds with spacers containing three, four, five, or six carbon atoms are denoted as 1–4, respectively. Gelation tests showed that the four compounds are versatile organogelators, and a subtle change in the length of the spacer can produce a dramatic change in the gelation behaviors of the compounds, as well as the micro-structures of the gel networks as revealed by SEM and XRD measurements. Within the 77 gel systems studied, at least seven of them, including 2/kerosene, 2/toluene, 2/xylene, 3/kerosene, 3/1-pentanol, 3/1-hexanol and 3/1-heptanol, gel spontaneously at room temperature. Furthermore, 2and 3can be used for the selective gelation of xylene or kerosene from their mixtures with water. Importantly, heating and cooling cycle or addition of a co-solvent is not necessary for the selective gelation. Furthermore, the gels of 2/xylene are mechanically strong enough for separation, and thereby it is believed that 2is a strong candidate for the practical separation of xylene from its mixture with water. FT-IR and temperature-dependent 1H NMR measurements demonstrated that inter-molecular hydrogen bonding plays an important role for the formation and maintenance of the gel networks. [ABSTRACT FROM AUTHOR]