کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5218469 | 1383328 | 2013 | 8 صفحه PDF | دانلود رایگان |

Direct O-alkylation of the parent compounds p-tert-butyldihomooxacalix[4]arene (1) and p-tert-butylhexahomotrioxacalix[3]arene (3) with 4-bromobutyronitrile and K2CO3 in acetonitrile afforded tetra- and tri-[(cyanopropyl)oxy] derivatives 2 and 4, respectively, as a mixture of conformers. These conformers were isolated and their conformational features studied by NMR spectroscopy (1H, 13C, COSY and NOESY) and DFT methods. Dihomooxacalix[4]arene tetra[(cyanobutyl)oxy] derivative 5 was also obtained and studied for comparison purposes. In general, good agreement was obtained between theoretical calculations and the NMR experimental data. For compounds 2 and 4 the partial cone conformation was the most stable, while the cone conformation was the most stable for derivative 5.
New homooxacalixarene cyano derivatives (2, 4 and 5), precursors to the synthesis of urea compounds, were synthesized and their conformational behaviour studied by NMR spectroscopy and DFT methods.
Journal: Tetrahedron - Volume 69, Issue 35, 2 September 2013, Pages 7430-7437