Stereoselective aziridination of cyclic allylic alcohols using chloramine-T.
نویسندگان
چکیده
The stereoselective aziridination of a range of cyclic allylic alcohols using two different chloramine salts (4-MeC(6)H(4)SO(2)NClNa, TsNClNa and t-BuSO(2)NClNa, BusNClNa) has been explored. The stereoselectivity of these reactions was highly dependent on the structure of the allylic alcohol and the chloramine salt. Generally, mixtures of cis- and trans-hydroxy aziridines were obtained, in which the major diastereomer was the cis-hydroxy aziridine, whilst complete cis-diastereoselectivity was observed in the aziridination of 1,3-disubstituted allylic alcohols. In each case studied, aziridination using BusNClNa gave higher cis-stereoselectivity than that observed for the same reaction using TsNClNa. Unexpectedly, application of the aziridination conditions to 1-substituted cyclopen-2-en-1-ols did not generate the aziridines. Instead, epoxy sulfonamides were obtained.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 6 23 شماره
صفحات -
تاریخ انتشار 2008