N-Halosuccinimides (NXS, 1) are efficiently activated in trifluoromethanesulfonic acid and BF(3)-H(2)O, allowing the halogenations of deactivated aromatics. Because BF(3)-H(2)O is more economic, easy to prepare, nonoxidizing, and offers sufficiently high acidity (-H(0) approximately 12, only slightly lower than that of trifluoromethanesulfonic acid), an efficient new electrophilic reagent combination of NXS/BF(3)-H(2)O has been developed. DFT calculations at the B3LYP/6-311++G//B3LYP/6-31G level suggest that protonated N-halosuccinimides undergo further protosolvation at higher acidities to reactive superelectrophilic species capable either in the transfer of X(+) from the protonated forms of NXS to the aromatic substrate or in forming a highly reactive and solvated X(+) which would readily react with the aromatic substrates. Structural aspects of the BF(3)-H(2)O complex have also been investigated.

Aromatics. -N-halosuccinimide/BF3·H2O mixtures are found to be efficient reagents for halogenation of deactivated arenes. DFT theoretical calculations show that superelectrophilic reagents are generated by multiple protonation of the N-halosuccinimides under the present conditions. -(PRAKASH*, G. K. S.; MATHEW, T.; HOOLE, D.; ESTEVES, P. M.; WANG, Q.; RASUL, G.; OLAH, G. A.; J. Am. Chem.

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Copper(II) complexes with substituted bis(salicylaldehyde) thiocarbohydrazones (3‐methoxy = H4LMe, 3‐ethoxy = H4LEt), have been synthesized. These ditopic ligands form dinuclear copper(II) complexes containing the ligands in their triplydeprotonated forms. The ligands entail two nonequivalent donor atom sites (ONN and ONS) for copper(II) coordination. Magnetic measurements of the complexes in the temperature range 2–290 K showed significant antiferromagnetic interactions between the two copper(II) ions, with –2J around 180 cm–1. The dinuclear molecules in turn also form face‐to‐face H‐bonded dimers involving four coppers in total.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)