The separation between a pair of peri-located dimethylamino and ethene-2,2-dinitrile groups in a naphthalene molecule, which models the progress of a Michael reaction, can be controlled by the installation of a short ethylene bridge or the introduction of repulsive interactions at the opposite set of peri positions. Introduction of a dimethylammonium substituent produced a hydrated chloride salt in which the Me₂N⋯C(H)C(CN)₂ separation between reactive groups decreases, reversibly, from 2.167 Å at 200 K to 1.749 Å at 100 K, with the maximum rate of change in the range 128–140 K, which was studied by variable temperature X-ray crystallography and solid state NMR. From these and other crystallographic data a correlation between Me₂N⋯C bond formation and alkene bond breaking was constructed for the first step of an aza-Michael reaction.

中文翻译：

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用含有周-周相互作用的结晶萘衍生物对aza-Michael反应进行建模：很长的N–C键？

可以通过安装短的乙烯桥或引入排斥相互作用来控制萘分子中一对位于周围的二甲基氨基和乙烯-2,2-二腈基团之间的分离在相反的一组周围位置。引入二甲基铵取代基产生了水合氯化物盐，其中Me ₂ N⋯C（H）C（CN）₂反应性基团之间的分离可逆地从200 K时的2.167Å降低至100 K时的1.749Å，最大变化率在128–140 K范围内，这是通过可变温度X射线晶体学和固态NMR研究的。根据这些和其他晶体学数据，为氮杂-迈克尔反应的第一步构建了Me ₂ N⋯C键形成与烯烃键断裂之间的相关性。