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in Wiley InterScience (www.interscience.wiley.com).The novel macrocyclic diamides 11-13, 16-18 are obtained in 45-66% yields by the reaction of dipotassium salts 10a-c and 15 with each of 1,4-di(bromomethyl)benzene 4, 2,6-di(bromomethyl)naphthalene 6 and 9,10-di(bromomethyl)anthracene 8, repectively, in boiling DMF. On the other hand, the new macrocyclic Schiff bases 28 and 29 are obtained in 44% and 42% yields by heating the appropriate bis-amines 25b, 26b with the corresponding bis-aldehydes 21, 22, respectively, in refluxing acetic acid under high-dilution conditions.

A new mild and efficient method for aromatic halogenation with a wide variety of halides in the presence of sodium bismuthate NaBO 3 in AcOH is reported. Metal halides of groups Ia, IIa, IIIa, IVa, Va, and the first row of transition elements are suitable for this method.There has been a growing interest in the last few years in metal halides as alternatives to molecular halogens in halogenations of aromatic compounds [1] [2]. Halides of transition metals of groups I, IV, and V have received particular attention [3 ± 6]. Generation of halogens from these metal halides requires very drastic conditions [7] [8]. Other methods involve oxidation of certain halides with hardly available and expensive oxidizing agents such as peroxyacetic acid [9], lead tetraacetate [10], and nitrogen dioxide [11].Bismuthate ion is a strong oxidizing agent, but little attention has been paid to its potential in organic synthesis [12]. It has long been known that the ion oxidizes halides to the corresponding halogen in aqueous HClO 4 [13] [14]. No studies have been carried out regarding the exploitation of the reagent in the halogenation of organic compounds with metal halides. XWe hereby wish to report a new method for aromatic chlorination and bromination with various halides in the presence of NaBiO 3 .Results and Discussion. ± Appropriate amounts of the aromatic substrate and the halide were allowed to react with NaBiO 3 in AcOH at room temperature. The reaction was monitored with a moist starch-iodide paper held over the reaction vessel. The blue color indicated the presence of free halogen in the reaction mixture.All metal halides of groups Ia, IIa, IIIa, IVa, Va, and the first row of transition metals react with NaBiO 3 in AcOH and produce the corresponding halogen. The reactivity of NaBiO 3 with halides varies from metal to metal. We found that the rate of halogen production increases as we go from the top of the group to the bottom. The reactivity is also affected by the amount of H 2 O present in the halide crystals. Anhydrous forms are more reactive than their hydrated forms.Naphthalene was chosen for a comparative study of aromatic chlorination and bromination with various metal chlorides and bromides. The results are summarized in Tables 1 and 2.

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P y r i d i n i u m D i c h l o r o b r o m a t e , A N e w B r o m i n a t i n g R e a g e n tAbstract: Pyridinium dichlorobromate (PyHBrCl 2 , 1) is a new example of iminium-trihalide complexes. The compound is prepared from pyridine and chlorine in the presence of aqueous hydrogen bromide. The crystalline trihalide is quite stable and acts as a safe source of positive bromine. It shows a remarkable reactivity towards aromatic compounds compared with other bromine complexes. It is also considered as a potential source for bromine chloride BrCl.