Yoshioka Eito, Imoto Yuuki, Yamaoka Yousuke, Ikeda Tomoko, Takahashi Hiroki, Tanaka Ryousuke, Hayashi Naoki, Miyabe Hideto
School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan.
Chemistry. 2024 Jun 25;30(36):e202400602. doi: 10.1002/chem.202400602. Epub 2024 Jun 3.
Radical-polar crossover reactions were studied for the intramolecular cyclopropanation of active methylene derivatives. In the presence of FeCl as a stoichiometric oxidant and KHPO as a base, the dehydrogenative cyclopropanation of active methylenes proceeded through the FeCl-promoted oxidative radical cyclization followed by the ionic cyclization to give the bicyclic cyclopropanes. The use of α-chloro-active methylenes leads the subcatalytic cyclopropanation involving two redox pathways. In the presence of KHPO, the redox cyclopropanation proceeded by using FeCl (20 mol%) in combination with ligand (20 mol%).
对活性亚甲基衍生物的分子内环丙烷化反应进行了自由基-极性交叉反应研究。在化学计量的氧化剂FeCl和碱KHPO存在下，活性亚甲基的脱氢环丙烷化反应通过FeCl促进的氧化自由基环化，随后进行离子环化，生成双环环丙烷。使用α-氯代活性亚甲基会导致涉及两条氧化还原途径的亚催化环丙烷化反应。在KHPO存在下，氧化还原环丙烷化反应通过使用20 mol%的FeCl与20 mol%的配体组合进行。
