Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison Wisconsin 53706, United States.
Photogreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
Org Lett. 2021 May 7;23(9):3496-3501. doi: 10.1021/acs.orglett.1c00938. Epub 2021 Apr 12.
Cyclobutyl moieties in drug molecules are rare, and in general, they are minimally substituted and stereochemically simple. Methods to assemble structurally complex cyclobutane building blocks suitable for rapid diversification are thus highly desirable. We report herein a photosensitized [2 + 2] cycloaddition with vinyl boronate esters affording straightforward access to complex, densely functionalized cyclobutane scaffolds. Mechanistic studies suggest an activation mode involving energy transfer to the styrenyl alkene rather than the vinyl boronate ester.
药物分子中的环丁基部分较为罕见，通常取代基较少，且立体化学结构简单。因此，人们非常希望开发出合适的方法来构建结构复杂的环丁烷砌块，以实现快速多样化。在此，我们报告了一种光诱导的[2+2]环加成反应，使用乙烯基硼酸酯作为亲偶极体，可以直接得到复杂的、多官能化的环丁烷骨架。机理研究表明，该反应的激活方式涉及到能量从激发态的苯乙烯向烯丙基转移，而不是乙烯基硼酸酯。
