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Abstract: Metal complexation to aryl (Ph, Cp, cyclobutadienyl) methylium cations, radicals, and anions was investigated using hybrid density functional theory methods (B3LYP/LANL2DZ), with a focus on the effects of substituents. The results of these calculations, in which both geometric and energetic consequences of adding substituents were examined, indicate that metal–methylium interactions are most sensitive to substituent effects for complexed cations. [Copyright &y& Elsevier]

Abstract: Syntheses of several (sulfonyl)methylphosphonate analogs of geranyl, neryl, and farnesyl diphosphates are described. Key steps include utilization of an (E)-selective Horner–Wadsworth–Emmons olefination which couples an aldehyde to the sulfone phosphonate moiety, and a selective reduction of the resulting dienyl sulfone phosphonate substrates. [Copyright &y& Elsevier]

A hybrid sequential molecular mechanics and quantum mechanical approach to modeling cyclic peptides has led to an effective method for predicting their 1 H and 13 C NMR chemical shift values. The method was first developed to predict chemical shifts in chloroform before being adapted to a more peptide friendly solvent, DMSO. Finally the effectiveness of this method was tested in a blind fashion and excellent agreement with the experimental NMR chemical shifts was observed. [ABSTRACT FROM AUTHOR]

Abstract: A process for synthesizing 1,4-benzodioxin, through oxidation of a phenol to an o-quinone followed by treatment with an enamine, has been developed. Adduct stereochemistry is found to be retained via this one-pot reaction. The method uses hypervalent iodine reagent under mild conditions and is compatible with a wide scope of phenols and enamines. [Copyright &y& Elsevier]