Ammonium-directed dihydroxylation: metal-free synthesis of the diastereoisomers of 3-aminocyclohexane-1,2-diol.
نویسندگان
چکیده
The ammonium-directed, metal-free oxidation of 3-(N,N-dibenzylamino)cyclohex-1-ene with mCPBA in the presence of either trichloroacetic acid or tosic acid has been used as the key step to facilitate the synthesis of all the diastereoisomers of 3-aminocyclohexane-1,2-diol, in >98% de in each case.
منابع مشابه
Ammonium-directed dihydroxylation of 3-aminocyclohex-1-enes: development of a metal-free dihydroxylation protocol.
Treatment of 3-aminocyclohex-1-enes with mCPBA in the presence of trichloroacetic acid gives the corresponding 1,2-anti-2,3-syn-1-trichloroacetoxy-2-hydroxy-3-aminocyclohexane with high levels of diastereoselectivity (90% de). This is consistent with a mechanism of oxidation involving hydrogen-bonded delivery of the oxidant by the allylic ammonium ion formed in situ, followed by highly regiosel...
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 6 20 شماره
صفحات -
تاریخ انتشار 2008