Oxidative Cleavage of Indoles Mediated by Urea Hydrogen Peroxide or H
<sub>2</sub>
O
<sub>2</sub>
in Polar Solvents
作者:Natalia Llopis、Patricia Gisbert、Alejandro Baeza
DOI:10.1002/adsc.202100214
日期:2021.7
The oxidative cleavage of indoles (Witkop oxidation) involving the use of H2O2 or urea hydrogen peroxide in combination with a polar solvent has been described. Among these solvents, 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) stands out as the one affording the corresponding 2-ketoacetanilides generally in higher yields The protocol described has also enabled the oxidation of different pyrroles and furans
已经描述了涉及使用 H 2 O 2或过氧化氢尿素与极性溶剂的吲哚的氧化裂解(Witkop 氧化)。在这些溶剂中,1,1,1,3,3,3-六氟异丙醇 (HFIP) 脱颖而出,通常以更高的产率提供相应的 2-酮乙酰苯胺。所描述的协议还能够氧化不同的吡咯和呋喃衍生物。此外,该程序是大规模实施的,从反应混合物中蒸馏出 HFIP 并重复使用(最多 4 个循环),而不会显着损害反应结果,这说明了其可持续性和适用性。