Photoinduced, Copper-Catalyzed Alkylation of Amides with Unactivated Secondary Alkyl Halides at Room Temperature
作者:Hien-Quang Do、Shoshana Bachman、Alex C. Bissember、Jonas C. Peters、Gregory C. Fu
DOI:10.1021/ja4126609
日期:2014.2.5
The development of a mild and general method for the alkylation of amides with relatively unreactive alkyl halides (i.e., poor substrates for SN2 reactions) is an ongoing challenge in organic synthesis. We describe herein a versatile transition-metal-catalyzed approach: in particular, a photoinduced, copper-catalyzed monoalkylation of primary amides. A broad array of alkyl and aryl amides (as well as
开发一种温和而通用的方法,用相对不活泼的卤代烷(即 SN2 反应的不良底物)对酰胺进行烷基化是有机合成中的一个持续挑战。我们在此描述了一种通用的过渡金属催化方法:特别是光诱导、铜催化的伯酰胺单烷基化。一系列广泛的烷基和芳基酰胺(以及内酰胺和 2-恶唑烷酮)与未活化的仲(和受阻伯)烷基溴和碘结合使用一组相对简单和温和的条件:廉价的 CuI 作为催化剂,无需单独添加配体,并在室温下形成 CN 键。该方法与多种官能团兼容,例如烯烃、氨基甲酸酯、噻吩和吡啶,并已应用于阿片受体拮抗剂的合成。一系列机械观察,包括反应性和立体化学研究,与耦合途径一致,包括铜-酰胺络合物的光激发,然后是电子转移以形成烷基。
Decarboxylative sp3 C–N coupling via dual copper and photoredox catalysis
作者:Yufan Liang、Xiaheng Zhang、David W. C. MacMillan
DOI:10.1038/s41586-018-0234-8
日期:2018.7
to construct sp2 carbon–nitrogen (C–N) bonds using palladium, copper or nickel catalysis1,2. However, the incorporation of alkyl substrates to form sp3 C–N bonds remains one of the major challenges in the field of cross-coupling chemistry. Here we demonstrate that the synergistic combination of coppercatalysis and photoredoxcatalysis can provide a general platform from which to address this challenge
Copper-Catalyzed Intermolecular Amidation and Imidation of Unactivated Alkanes
作者:Ba L. Tran、Bijie Li、Matthias Driess、John F. Hartwig
DOI:10.1021/ja411912p
日期:2014.2.12
evidenced by the catalytic reaction of cyclohexane with benzamide in the presence of CBr4, which formed exclusively bromocyclohexane. Furthermore, stoichiometric reactions of [(phen)Cu(phth)2] with tBuOOtBu and (Ph(Me)2CO)2 at 100 °C without cyclohexane afforded N-methylphthalimide (Me-phth) from β-Me scission of the alkoxyradicals to form a methylradical. Separate reactions of cyclohexane and d12-cyclohexane
Stereoselective direct reductive amination of ketones with electron-deficient amines using Re2O7/NaPF6 catalyst
作者:Braja Gopal Das、Prasanta Ghorai
DOI:10.1039/c3ob40918j
日期:——
The first example of direct reductive amination (DRA) of ketones with electron-deficient amines (EDA) such as Cbz-, Boc-, EtOCO-, Fmoc-, Bz-, ArSO2-, etc. protected amines have been achieved using catalytic Re2O7/NaPF6. Excellent chemoselectivities as well as diastereoselectivity (for 2-alkyl cyclohexanones) were obtained.
[
<sup>11</sup>
C]Carbonyl Difluoride—a New and Highly Efficient [
<sup>11</sup>
C]Carbonyl Group Transfer Agent
作者:Jimmy E. Jakobsson、Shuiyu Lu、Sanjay Telu、Victor W. Pike
DOI:10.1002/anie.201915414
日期:2020.4.27
Herein, the synthesis and use of [11 C]carbonyl difluoride for labeling heterocycles with [11 C]carbonyl groups in high molar activity is described. A very mild single-pass gas-phase conversion of [11 C]carbon monoxide into [11 C]carbonyl difluoride over silver(II) fluoride provides easy access to this new synthon in robust quantitative yield for labeling a broad range of cyclic substrates, for example
本文描述了 [11 C] 羰基二氟化物的合成和用途,用于以高摩尔活性标记具有 [11 C] 羰基的杂环。在氟化银 (II) 上将 [11 C] 一氧化碳转化为 [11 C] 羰基二氟化物的非常温和的单程气相转化提供了以稳健的定量产率轻松获得这种新合成子的方法,用于标记广泛的环状底物,例如,咪唑烷-2-酮、噻唑烷-2-酮和恶唑烷-2-酮。标记反应可以利用接近化学计量的前体量和在室温下在多种溶剂中的短反应时间,同时还显示出高水耐受性。整个放射合成协议既简单又可重复。所需的设备可以由广泛可用的部件构成,因此非常适合用于 PET 放射性示踪剂生产的自动化。我们预计这种简单的方法将在放射化学界获得 PET 放射性示踪剂合成的广泛认可。