کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5283064 | 1385706 | 2006 | 4 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Kinetically and thermodynamically controlled synthesis of tetraoxa[14]metacyclophanes and hexaoxa[16]metacyclophanes
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The nucleophilic aromatic substitution of 1,5-difluoro-2,4-dinitrobenzene with 2-propylresorcinol in Et3N/CH3CN produces a mixture of syn and anti conformers of the cyclic tetramer and the cyclic hexamer with a kinetically controlled product distribution. Moreover, the reaction in DMF was catalyzed by CsF to also produce a mixture of these cyclic oligomers. In this case, however, the C-O bond is cleaved by the fluoride ion and the cyclization reaction is reversible; therefore, in the presence of excess CsF, the thermodynamically favored product (syn-isomer of cyclic tetramer) is obtained as the major product. The structures of the two conformational isomers of cyclic tetramers were determined by X-ray crystallography.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Tetrahedron Letters - Volume 47, Issue 24, 6 June 2006, Pages 4041-4044
Journal: Tetrahedron Letters - Volume 47, Issue 24, 6 June 2006, Pages 4041-4044
نویسندگان
Hisatoshi Konishi, Kazunari Tanaka, Yuki Teshima, Takayuki Mita, Osamu Morikawa, Kazuhiro Kobayashi,