Regioselective bromination of fused heterocyclic N-oxides.
نویسندگان
چکیده
A mild method for the regioselective C2-bromination of fused azine N-oxides is presented, employing tosic anhydride as the activator and tetra-n-butylammonium bromide as the nucleophilic bromide source. The C2-brominated compounds are produced in moderate to excellent yields and with excellent regioselectivity in most cases. The potential extension of this method to other halogens, effecting C2-chlorination with Ts(2)O/TBACl is also presented. Finally, this method could be incorporated into a viable one-pot oxidation/bromination process, using methyltrioxorhenium/urea hydropgen peroxide as the oxidant.
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ورودعنوان ژورنال:
- Organic letters
دوره 15 4 شماره
صفحات -
تاریخ انتشار 2013