کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1346688 | 1500366 | 2010 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The first enantioselective [3+2] cycloaddition of epoxides to arylisocyanates: asymmetric synthesis of chiral oxazolidinone phosphonates
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موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی معدنی
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چکیده انگلیسی
A [3+2] cycloaddition of diethyl 1,2-oxiranephosphonate to aryl isocyanates catalyzed by lanthanide cations is described. The reaction is highly regioselective and 5-substituted 2-oxazolidinone phosphonates are obtained with a regioselectivity greater than 95:5 with respect to the 4-substituted regioisomer, and in up to 84% yield. When 20 mol % of Pybox-Yb3+ is used as a catalyst, enantiomerically enriched products are obtained in up to 75% ee, depending on the reaction conditions, and the nature of the isocyanate. Low temperatures benefit asymmetric induction, but have an adverse effect on the regioselectivity for para-substituted aryl isocyanates.
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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Tetrahedron: Asymmetry - Volume 21, Issues 21–22, 25 November 2010, Pages 2746–2752
Journal: Tetrahedron: Asymmetry - Volume 21, Issues 21–22, 25 November 2010, Pages 2746–2752
نویسندگان
Maria Teresa Barros, Ana Maria Faísca Phillips,