Iodine/DMSO promoted oxidation of benzylic Csp3–H bonds to diketones – A mechanistic investigation
作者:Janeeka Jayram、Bheki A. Xulu、Vineet Jeena
DOI:10.1016/j.tet.2019.130617
日期:2019.10
an α-methylene ketone. The electron paramagnetic resonance (EPR) spectrum centred at g = 2.0011 supports the involvement of iodine and benzylic radicals, as the α-iodinated compound 2-iodo-1,2-diphenylethanone was isolated as a key reactive intermediate. The oxidation reaction relies, primarily, on DMSO as a source of oxygen in benzil, proven by the reaction of benzylphenyl ketone with diphenyl sulfoxide
An iodine/DMSO-catalyzed sequential one-pot approach to 2,4,5-trisubstituted-1<i>H</i>-imidazoles from α-methylene ketones
作者:Janeeka Jayram、Vineet Jeena
DOI:10.1039/c8ra07238h
日期:——
A sequential one-pot approach to 2,4,5-trisubstituted imidazoles has been developed from α-methylene ketones and aldehydes. This methodology employs air-moisture stable reaction conditions and an inexpensive iodine/DMSO system affording a diverse range of known and novel (substrate scope) 2,4,5-trisubstituted imidazoles in moderate to excellent yields. The iodine/DMSO system was extended to the domino
Synthesis of <i>N</i>-alkoxyphthalimide derivatives <i>via</i> PIDA-promoted cross dehydrogenative coupling reaction
作者:Rongxiang Chen、Bing Liu、Wenbo Li、Kai-Kai Wang、Changqing Miao、Zhizhuang Li、Yingjie Lv、Lantao Liu
DOI:10.1039/d1ra00375e
日期:——
cross-dehydrogenative couplingreaction between N-hydroxyphthalimide (NHPI) and aryl ketones for efficient synthesis of N-alkoxyphthalimide products in moderate to good yields has been described. This methodology is distinguished by catalyst-free conditions, readily available starting materials, wide substrate scope and operational simplicity. In addition, a gram-scale reaction and synthetic transformation
Electrochemical oxidation-induced benzyl C H carbonylation for the synthesis of aromatic α-diketones
作者:Yu-Fang Tan、Yuan Chen、Rui-Xue Li、Zhi Guan、Yan-Hong He
DOI:10.1016/j.tetlet.2021.153593
日期:2022.1
direct carbonylation of benzyl CH bond for the synthesis of aromatic α-diketones is described. In this process, tetrabutylammonium iodide (nBu4NI) not only acts as an electrolyte, but its iodine anion is oxidized to an iodine radical at the anode, acting as a hydrogen atom transfer agent. The iodine radical extracts the benzyl hydrogen atom and causes the carbonylation of the benzyl position, where O2 in
描述了电化学氧化诱导的苄基 C H 键直接羰基化合成芳族 α-二酮。在这个过程中,四丁基碘化铵(n Bu 4 NI)不仅起到电解质的作用,而且其碘阴离子在阳极被氧化成碘自由基,起到氢原子转移剂的作用。碘自由基提取苄基氢原子并引起苄基位置的羰基化,其中空气中的O 2用作氧源。
Silver‐Catalyzed Coupling of Two CH Groups and One‐Pot Synthesis of Tetrasubstituted Furans, Thiophenes, and Pyrroles
作者:Shuai Mao、Xue‐Qing Zhu、Ya‐Ru Gao、Dong‐Dong Guo、Yong‐Qiang Wang
DOI:10.1002/chem.201501410
日期:2015.8.3
Silver‐catalyzedcoupling of twoCHgroups to form 1,4‐diketones have been developed for the first time. The resultant ketones then undergo cyclization to synthesize tetrasubstitutedfurans, thiophenes, and pyrroles from benzyl ketone derivatives in a one‐pot reaction process. This highly‐efficient synthetic method, which utilizes air as the terminal oxidant and readily accessible starting materials