Laboratoire de Chimie Théorique, CNRS UMR 7616, Université Pierre et Marie Curie, Case Courrier 137, 4, place Jussieu, 75252 Paris Cedex 05, France.
J Org Chem. 2010 Mar 5;75(5):1427-36. doi: 10.1021/jo902315t.
The interaction between 1-propynyllithium, taken as a model of sp organolithium compound, and formaldehyde has been investigated with DFT theoretical methods. The unsolvated monomer, homogeneous dimer, trimer, tetramer, and hexamer have been considered, as well as the mixed aggregates with lithium dimethylamide in various oligomeric forms. In most cases, the separate entities, their docking complexes, the transition states, and the condensation products have been characterized. Overall, the general reaction scheme remains the same whatever the hybridization and the aggregation. However, the dimeric sp nucleophiles are expected to be more reactive (at least in kinetic conditions), while monomeric sp(3) entities would be the best nucleophiles in kinetic and thermodynamic conditions, even if its docking is the least exothermic. This work also suggests that the aggregation plays a relatively limited role on the model reaction.
采用 DFT 理论方法研究了 1-丙炔基锂（作为 sp 有机锂化合物的模型）与甲醛之间的相互作用。考虑了非溶剂化单体、均相二聚体、三聚体、四聚体和六聚体，以及各种齐聚形式的与二甲基酰胺锂的混合聚集体。在大多数情况下，对单独的实体、它们的对接复合物、过渡态和缩合产物进行了表征。总的来说，无论杂化和聚集如何，一般的反应方案保持不变。然而，二聚 sp 亲核试剂预计具有更高的反应性（至少在动力学条件下），而单体 sp(3)实体将是动力学和热力学条件下的最佳亲核试剂，即使其对接的放热最少。这项工作还表明，聚集在模型反应中仅起到相对有限的作用。
