α,ω-Bis(3,6-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-yl)alkanes and products of their cyclization, pyrimidinophanes: intra- and intermolecular interaction in crystals and in solutions
作者:V. E. Semenov、O. A. Lodochnikova、A. T. Gubaidullin、O. N. Kataeva、A. V. Chernova、Y. Ya. Efremov、S. V. Kharlamov、Sh. K. Latypov、V. S. Reznik
DOI:10.1007/s11172-008-0019-6
日期:2008.1
the presence of intramolecular interactions in chloroform solutions of α,ω-bis(3,6-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-yl)alkanes and pyrimidinophanes were made based on the UV spectra, which were interpreted in terms of hypo- and hyperchromic effects relatively to the model uracil derivative. These conclusions correlate with the X-ray data: there are no intramolecular π-π contacts between
α,ω-双(3,6-二甲基-2,4-二氧代-1,2,3,4-四氢嘧啶-1-基)烷烃与多聚甲醛反应生成嘧啶烷,其中包含四个 3,6-二甲基尿嘧啶片段,通过亚甲基链相互连接。对晶体状态和溶液中“开放”和大环尿嘧啶衍生物的分子内和分子间相互作用进行了比较研究。根据核磁共振谱数据,氯仿溶液中没有“开放”和大环化合物的自缔合,而 X 射线数据揭示了这些晶体中 3,6-二甲基尿嘧啶碎片之间的分子间 π-π 接触。化合物。关于 α,ω-双(3,6-二甲基-2,4-二氧-1,2,3, 4-四氢嘧啶-1-基)烷烃和嘧啶并烷是基于紫外光谱制备的,根据相对于模型尿嘧啶衍生物的减色和增色效应进行解释。这些结论与 X 射线数据相关:晶体和“开放”化合物溶液中的 3,6-二甲基尿嘧啶片段之间没有分子内 π-π 接触,这些片段在分子中的相对位置嘧啶并烷的数量由聚亚甲基桥的长度定义。对于具有三亚甲基和六亚甲基链的大环,观