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A simple and efficient method for transition-metal-free N-arylation of various amines by triarylsulfonium triflates is described. Both aliphatic and aromatic amines were smoothly converted at 80 °C in the presence of tBuOK or KOH to give the corresponding mono N-arylated products in good to high yields. The molar ratios of the reactants and the choice of bases had a big effect on the reaction. When a large excess of [Ph S][OTf] and tBuOK were employed for primary amines under the standard conditions, the bis(N-phenyl) products were predominantly formed. This method was also applicable to the synthesis of bioactive N-phenyl amino acid derivatives. The control experiments, the deuterium labelling study, and the presence of regioisomers of N-arylated products when using 4-substituted triarylsulfonium triflates suggested that the reaction might proceed through an aryne intermediate. The present protocol demonstrated that triarylsulfonium salts are versatile arylation reagents in the construction of C -N bonds.

A new water-soluble salicylaldehyde-2-sulfobenzoylhydrazone Schiff base anion ligand (HL-) has been designed and synthesized. The reaction of HL- with Zn(OAc)2·2H2O, CoCl2·6H2O, MnCl2·4H2O, NiSO4·7H2O, and Cu(OAc)2·H2O or CuBr2 led to the formation of five novel binuclear complexes, namely, [Zn2(L2-)2(H2O)4](H2O)4 (1), [Co2(L2-)2(H2O)4](H2O)4 (2), [Mn2(L2-)2(H2O)4](H2O)4 (3), [Ni2(L2-)2(H2O)4](H2O)2 (4), and [Cu2(L2-)2(H2O)2](H2O)12 (5), which were characterized by IR spectroscopy, elemental analyses, and X-ray crystallography. Structural investigations of complexes 1−5 revealed that the introduction of a hydrophilic group −SO3 - to the benzoyl ring of salicylaldehyde-benzoylhydrazone facilitates intermolecular infinite hydrogen-bonding interactions, which lead to the formation of supramolecular networks and a dodecameric water cluster in the crystalline solid 5. Moreover, the electronegative −SO3 - group in the ligand acts as a counteranion to balance the charge of frameworks, causing the ligand to coordinate metal ions through the oxygen of a protonated amide functionality rather than that of the deprotonated form and keeping additional anions out of these crystallization frameworks.

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A facile synthetic approach to 3'-substituted-5-cyclopropanespirohydantoins has been developed and used to synthesize some new spirohydantoins. The key aspect is the preparation of -carboethoxy isocyanate basing on Curtius rearrangement, which can be ring-closed to the expected spirohydantoins after the reaction with various amines and hydrazines. Interestingly the cyclopropane ring doesn't open during the whole process.