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Bromine-Catalyzed Aziridination of Olefins. A Rare Example of Atom-Transfer Redox Catalysis by a Main Group Element.-Treatment of various olefins and olefinic alcohols with chloramine-T as nitrogen source in the presence of PhNMe 3 + Br 3 − catalyst provides good to excellent yields of aziridines. 1,2-Disubstituted olefins give the corresponding aziridines stereospecifically.-(JEONG, J. U.; TAO, B.; SAGASSER, I.; HENNIGES, H.; SHARPLESS, K. B.; J. Am. Chem. Soc. 120 (1998) 27, 6844-6845; Dep. Chem., Scripps Res. Inst.,

stereochemistry stereochemistry (general, optical resolution) O 0030 -029(Phosphino-oxazoline)copper(II) Complexes as Chiral Catalysts for Enantioselective Diels-Alder Reactions. -The Diels-Alder reaction of simple cyclic dienes with 3-acryloyl-1,3-oxazolidin-2-ones such as in the presence of chiral (phosphino-oxazoline)copper(II) complexes with bulky aryl groups at the phosphorus is investigated. In general, good to high endo-selectivities are obtained with enantioselectivities up to 97% e.e. With the anthracenyl substituted ligand unexpectedly the exo-endo selectivity is found to be reversed. - (SAGASSER, I.; HELMCHEN, G.; Tetrahedron Lett. 39 (1998) 3-4, 261-264; Org.-Chem. Inst., Ruprecht-Karls-Univ., D-69120 Heidelberg, Germany; EN)