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A new, selective, straightforward and general method for preparation of highly functionalized coronands or spiro derivatives bearing 1,2-dihydroxyacetophenone unit, under conventional conditions and ultrasonic irradiation, is reported. The reaction setup involves only one step, acylation of an α-chloro-3,4-dihydroxyacetophenone with phthaloyl dichloride derivatives. 1,3- and 1,4-Phthaloyl dichloride derivatives leads to coronands only, while 1,2-phthaloyl dichlorides lead either to coronands or to spiro derivatives. A feasible explanation for the different behavior between conventional and ultrasound methods could be the different reaction mechanism involved in the two procedures: tetrahedral nucleophilic substitution under conventional conditions and radical substitution under ultrasound. Ultrasound induces a remarkable acceleration of the reactions (from days to minutes) and, most significantly, the yields are twice as high. A feasible explanation for the efficiency of the reactions under ultrasonic irradiation is presented.

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Pyridazine derivatives R 0500Diazinium Salts with Dihydroxyacetophenone Skeleton: Syntheses and Antimicrobial Activity. -Cycloimmonium salts [(III) and (V)] are synthesized starting from chloroacetophenone (I) using microwave and ultrasound irradiation. All compounds have an excellent antibacterial activity, and most of them a good antifungal activity. -(BALAN, A. M.; FLOREA, O.; MOLDOVEANU, C.; ZBANCIOC, G.; IUREA, D.; MANGALAGIU*, I. I.; Eur. J. Med. Chem. 44 (2009) 5, 2275-2279; Org. Biochem. Dep., Al. I. Cuza Univ., RO-700506 Iasi, Rom.; Eng.) -R. Langenstrassen 34-156