Introduction of C-Sulfonate Groups into Disaccharide Derivatives

To prepare C-sulfonate derivatives of disaccharides two different strategies were followed. Thus 6- and 6′-C-sulfocellobiosides 4 and 10–12 were prepared starting from a suitably protected cellobioside. The 6′-C-sulfoaminocellobioside 18 was prepared by construction of the molecule through a glycosylation reaction. In both cases, the synthetic pathway involves regioselective tosylation, introduction of a sulfur atom by nucleophilic displacement with potassium thioacetate and oxidation with hydrogen peroxide.     

Projecting average family size in rural India by the analytic hierarchy process

In this study, cultural, economic as well as certain crucial demographic factors are considered as the determinants for projecting the average family size in rural India. We use the Analytic Hierarchy Process to analyze influences of the factors which enter implicitly in a rural couple's decision‐making to determine the number of children they want to have as time goes by. We did not attempt to make distinctions among the regional differences in rural India. The outcome projected in our analysis compares favorably with the results of other demographic studies.     

Liquid crystalline properties and photochromism of 4-alkyl-N-(4-alkloxysalicylidene)anilines

Eight new homologous series of 4-alkyl-N-(4-alkloxysalicylidene)anilines were synthesized. The phase transitions of these homologues were determined using differential scanning calorimetry and polarizing optical microscopy. The homologues began to exhibit liquid crystalline phases as the terminal alkyl or alkoxyl chains were lengthened. In addition, some members of these homologues series exhibited photochromism in the solid state.     

An unusual substitution reaction of an aromatic sulfonic group based on 3-carbonyl-4-phenolsulfonic acid

An unusual substitution reaction of an aromatic sulfonic group based on 3-carbonyl-4-phenolsulfonic acid was discovered in a diazo-coupling process.The reaction occurred under mild reaction conditions (pH 8.0-9.0.0-5 C,solvent:water) within a short reaction time(1h).A plausible substitution reaction mechanism by phenol-ketone resonance was proposed.     

Exploring the Reactivity of a Frustrated Sn/P Lewis Pair: The Highly Selective Complexation of the cis-Azobenzene Photoisomer

The reactivity of the geminal frustrated Lewis pair (FLP) (F₅C₂)₃SnCH₂P(tBu)₂ ( 1 ) was explored by reacting it with a variety of small molecules (PhOCN, PhNCS, PhCCH, tBuCCH, H₃CC(O)CH=CH₂, Ph[C(O)]₂Ph, PhN=NPh and Me₃SiCHN₂), featuring polar or non-polar multiple bonds and/or represent α,β-unsaturated systems. While most adducts are formed readily, the binding of azobenzene requires UV-induced photoisomerization, which results in the highly selective complexation of cis-azobenzene. In the case of benzil, the reaction does not lead to the expected 1,2- or 1,4-addition products, but to the non-stereoselective (tBu)₂PCH₂-transfer to a prochiral keto function of benzil. All adducts of 1 were characterised by means of multinuclear NMR spectroscopy, elemental analyses and X-ray diffraction experiments.     

Irradiation of detonation nanodiamonds with γ-rays does not produce long living spin radicals

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Reagent‐ and Metal‐Free Anodic C−C Cross‐Coupling of Aniline Derivatives

The dehydrogenative cross‐coupling of aniline derivatives to 2,2′‐diaminobiaryls is reported. The oxidation is carried out electrochemically, which avoids the use of metals and reagents. A large variety of biphenyldiamines were thus prepared. The best results were obtained when glassy carbon was used as the anode material. The electrosynthetic reaction is easily performed in an undivided cell at slightly elevated temperature. In addition, common amine protecting groups based on carboxylic acids were employed that can be selectively removed under mild conditions after the cross‐coupling, which provides quick and efficient access to important building blocks featuring free amine moieties.