Reactive ketenes through a carbonate/amine shuttle deprotonation strategy: catalytic, enantioselective alpha-bromination of acid chlorides.
نویسندگان
چکیده
[reaction: see text] We have developed an efficient methodology for the generation of ketenes by employing a catalytic shuttle base and potassium carbonate as a stoichiometric base. We have applied this technology to the catalytic, asymmetric alpha-bromination of acid chlorides.
منابع مشابه
Generation of ketenes from acid chlorides using NaH/crown ether shuttle-deprotonation for use in asymmetric catalysis.
[reaction: see text] We describe methodology for the in situ generation of reactive monosubstituted ketenes from acid chlorides through a shuttle deprotonation process using NaH as an inexpensive stoichiometric base and a crown ether cocatalyst. We have successfully applied this new procedure to the catalytic, asymmetric synthesis of beta-lactams and alpha-haloesters.
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ورودعنوان ژورنال:
- Organic letters
دوره 3 13 شماره
صفحات -
تاریخ انتشار 2001