Chirale Azidoselenide wie 2 sind nützliche Ausgangsverbindungen für die Synthese enantiomerenangereicherter stickstoffhaltiger Produkte, z. B. 3. Die Azidoselenide 2 sind durch asymmetrische elektrophile Azidoselenylierung von Alkenen mit dem chiralen schwefelhaltigen Selenyltriflat 1 und Natriumazid zugänglich, in vielen Fällen mit hoher Seitenselektivität.

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[reaction: see text] The first example of a kinetic resolution process promoted by electrophilic selenium reagents is reported. Racemic allylic alcohols react with half equivalents of a selenenylating agent in methanol leading to the regiospecific formation of the corresponding addition products with a very high level of facial selectivity (from 95:5 to 98:2 dr). The unreacted alcohols can be recovered in an optically enriched form (from 90 to 94% ee).

Keywords: Asymmetric electrophilic additions / Chiral selenenylating reagents / Noncovalent interactions / Selenium / Sulfur Chiral sulfur-containing electrophilic selenium reagents can be employed to effect efficient asymmetric syntheses. Spectroscopic and chemical evidence demonstrate that the observed high selectivity of the asymmetric reactions is associ-

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Chiral, nonracemic azidoselenides such as 2 are useful intermediates for the synthesis of enantiomerically enriched nitrogen‐containing compounds (e.g. 3). The asymmetric electrophilic azidoselenenylation of a variety of alkenes with the sulfur‐containing chiral selenenyl triflate 1 and sodium azide occurred with high facial selectivity to provide an array of azidoselenides, which were further elaborated.

By reaction with ammonium persulfate the easily available diselenide derived from (1R)‐(+)‐camphor was converted into the camphorselenenyl sulfate. This chiral nonracemic electrophilic selenium reagent reacted with alkenes, at 40 °C in acetonitrile in the presence of water, to afford the selenohydroxylated adducts in good yields and with moderate to good facial selectivity. The two diastereomeric addition products could be separated in most cases.

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