Multifunctional chiral phosphines-catalyzed highly diastereoselective and enantioselective substitution of Morita-Baylis-Hillman adducts with oxazolones.
نویسندگان
چکیده
Multifunctional chiral phosphine (phosphine-thiourea type) L2-catalyzed allylic substitutions of MBH adducts 1 with oxazolones 2 produce the corresponding optically active adducts 3 in good to excellent yields and ee's as well as moderate to good de's under mild conditions. The synergistic interaction between hydrogen bond donor site and nucleophilic site has been discussed, indicating that finely tuning the active sites of the multifunctional phosphine organocatalysts is very important.
منابع مشابه
Nucleophilic Chiral Phosphines: Powerful and Versatile Catalysts for Asymmetric Annulations.
Recent advances in chiral-phosphine-catalyzed asymmetric annulation reactions; including annulations of allenes, alkynes, Morita-Baylis-Hillman (MBH) carbonates, and ketenes; and their applications in the synthesis of bioactive molecules and natural products are reviewed.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 9 9 شماره
صفحات -
تاریخ انتشار 2011