Urea derivatives are highly active catalysts for the base-mediated generation of terminal epoxides from aldehydes and trimethylsulfonium iodide.
نویسندگان
چکیده
N,N'-Diarylureas have been shown to efficiently catalyse sulfonium ylide-mediated aldehyde epoxidation reactions for the first time. These processes are of broad scope and can be coupled with a subsequent Cu(II) ion-catalysed Meinwald rearrangement to give an efficient and convenient protocol for aldehyde homologation without intermediate purification.
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متن کاملB-podands as efficient catalysts for the ring opening of epoxides in water: A versatile and atom economical method for the synthesis of vicinal azidoalcohols
For the first time B-podands have been studied as an efficient and powerful catalysts in the ring opening of epoxides with azide anion in water. The reaction afforded the corresponding 1,2-azidoalcohols with high regioselectivity under mild reaction conditions and in a highly atom economic fashion.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 6 8 شماره
صفحات -
تاریخ انتشار 2008