1187926-98-2Relevant articles and documents
Hydrogen-Bonding Catalyzed Ring-Closing C?O/C?O Metathesis of Aliphatic Ethers over Ionic Liquid under Metal-Free Conditions
Wang, Huan,Zhao, Yanfei,Zhang, Fengtao,Wu, Yunyan,Li, Ruipeng,Xiang, Junfeng,Wang, Zhenpeng,Han, Buxing,Liu, Zhimin
supporting information, p. 11850 - 11855 (2020/05/16)
O-heterocycles have wide applications, and their efficient and green synthesis is very interesting. Herein, we report hydrogen-bonding catalyzed ring-closing metathesis of aliphatic ethers to O-heterocycles over ionic liquid (IL) catalyst under metal- and solvent-free conditions. The IL 1-butylsulfonate-3-methylimidazolium trifluoromethanesulfonate ([SO3H-BMIm][OTf]) is discovered to show outstanding performance, better than the reported catalysts. An interface effect plays an important role in mediating the reaction rate due to the immiscibility between the products and the IL catalyst, and the products can be spontaneously separated. NMR analysis and DFT calculation suggest that a pair of cation and anion of [SO3H-BMIm][OTf] could form three strong H-bonds with an ether molecule, which catalyze the ether transformation via a cyclic oxonium intermediate. A series of O-heterocycles including tetrahydrofurans, tetrahydropyrans, morpholines and dioxane can be obtained from their corresponding ethers in excellent yields (e.g., >99 %). This work opens an efficient and metal-free way to produce O-heterocycles from aliphatic ethers.
Deaminative Reductive Arylation Enabled by Nickel/Photoredox Dual Catalysis
Yi, Jun,Badir, Shorouk O.,Kammer, Lisa Marie,Ribagorda, Mariá,Molander, Gary A.
supporting information, (2019/05/07)
Described is a cross-electrophilic, deaminative coupling strategy harnessing Katritzky salts as a new species of electrophile in Ni/photoredox dual catalytic reductive cross-coupling reactions. Distinguishing features of this arylation protocol include its mild reaction conditions, high chemoselectivity, and adaptability to a variety of complex substrates [i.e., pyridinium salts derived from amines and partners derived from (hetero)aryl bromides].
Ru/Ni Dual Catalytic Desulfinative Photoredox Csp2-C sp3Cross-Coupling of Alkyl Sulfinate Salts and Aryl Halides
Knauber, Thomas,Chandrasekaran, Ramalakshmi,Tucker, Joseph W.,Chen, Jinshan Michael,Reese, Matthew,Rankic, Danica A.,Sach, Neal,Helal, Christopher
supporting information, p. 6566 - 6569 (2017/12/26)
A mild Ru/Ni dual catalytic desulfinative photoredox Csp2-Csp3 cross-coupling reaction of alkyl sulfinate salts with aryl halides has been developed. The optimized catalyst system, consisting of Ru(bpy)3Cl2, Ni(COD)2, and DBU, smoothly mediates the coupling of a diverse set of secondary and primary nonactivated alkyl sulfinate salts with a broad range of electron-deficient aryl bromides, electron-rich aryl iodides, and heteroaryl bromides under irradiation with blue light. The procedure is ideal for late-stage introduction of alkyl groups on pharmaceutical intermediates, and the Csp2-Csp3 cross-coupling reaction allowed the rapid synthesis of caseine kinase 1 inhibitor analogues via a parallel medicinal chemistry effort.
