Sinnwell Michael A, Groeneman Ryan H, Ingenthron Benjamin J, Li Changan, MacGillivray Leonard R
Department of Chemistry, University of Iowa, Iowa City, IA, USA.
Department of Biological Sciences, Webster University, St. Louis, MO, USA.
Commun Chem. 2021 May 10;4(1):60. doi: 10.1038/s42004-021-00493-3.
Methods to form cyclobutane rings by an intermolecular [2 + 2] cross-photoreaction (CPR) with four different substituents are rare. These reactions are typically performed in the liquid phase, involve multiple steps, and generate product mixtures. Here, we report a CPR that generates a cyclobutane ring with four different aryl substituents. The CPR occurs quantitatively, without side products, and without a need for product purification. Generally, we demonstrate how face-to-face stacking interactions of aromatic rings can be exploited in the process of cocrystallization and the field of crystal engineering to stack and align unsymmetrical alkenes in CPRs to afford chiral cyclobutanes with up to four different aryl groups via binary cocrystals. Overall, we expect the process herein to be useful to generate chiral carbon scaffolds, which is important given the presence of four-membered carbocyclic rings as structural units in biological compounds and materials science.
通过分子间[2 + 2]交叉光反应（CPR）形成具有四个不同取代基的环丁烷环的方法很少见。这些反应通常在液相中进行，涉及多个步骤，并产生产物混合物。在此，我们报道了一种CPR，它能生成具有四个不同芳基取代基的环丁烷环。该CPR定量发生，无副产物，且无需产物纯化。一般来说，我们展示了在共结晶过程和晶体工程领域中，如何利用芳香环的面对面堆积相互作用，在CPR中堆积和排列不对称烯烃，通过二元共晶体得到具有多达四个不同芳基的手性环丁烷。总体而言，我们预计本文所述方法对于生成手性碳骨架将是有用的，鉴于四元碳环作为生物化合物和材料科学中的结构单元的存在，这一点很重要。
