Umpolung of Carbonyl Groups as Alkyl Organometallic Reagent Surrogates for Palladium-Catalyzed Allylic Alkylation
作者:Dianhu Zhu、Leiyang Lv、Chen-Chen Li、Sosthene Ung、Jian Gao、Chao-Jun Li
DOI:10.1002/anie.201809112
日期:2018.12.10
carbon nucleophiles is difficult and remains a major challenge. Reported here is a highly chemo‐ and regioselective direct palladium‐catalyzed C‐allylation of hydrazones, generated from carbonyls, as a source of umpolung unstabilized alkyl carbanions and surrogates of alkyl organometallicreagents. Contrary to classical allylation techniques, this umpolung reaction utilizes hydrazones prepared not
Chemo- and Regioselective C(sp<sup>3</sup>)H Arylation of Unactivated Allylarenes by Deprotonative Cross-Coupling
作者:Nusrah Hussain、Gustavo Frensch、Jiadi Zhang、Patrick J. Walsh
DOI:10.1002/anie.201309084
日期:2014.4.1
Transmetalation of the resulting allyllithium intermediate to LPdAr(Br) and reductive elimination provide the 1,1‐diarylprop‐2‐enes, which are not accessible by the Heck reaction. The regioselectivity in this deprotonative cross‐coupling process is catalyst‐controlled and very high.
Cu(I)-Catalyzed, α-Selective, Allylic Alkylation Reactions between Phosphorothioate Esters and Organomagnesium Reagents
作者:Andrew M. Lauer、Farzeen Mahmud、Jimmy Wu
DOI:10.1021/ja202954b
日期:2011.6.15
of allylic alkylation reactions involving hard nucleophiles remains a significant challenge and continues to be an active area of research. The lack of general methods in which α-alkylation is favored underscores the need for the development of new processes for achieving this type of selectivity. We report that Cu(I) catalyzes the allylic substitution of phosphorothioate esters with excellent α-regioselectivity
Copper-catalyzed asymmetric allylic substitution with aryl and ethyl Grignard reagents
作者:Khalid B. Selim、Ken-ichi Yamada、Kiyoshi Tomioka
DOI:10.1039/b809140d
日期:——
Phenyl- and ethyl-magnesium bromides undergo regioselective asymmetricallylicsubstitution with high enantioselectivity under the catalysis of chiral amidophosphane-copper(I) complexes.
Controllable, Sequential, and Stereoselective C–H Allylic Alkylation of Alkenes
作者:Ling Qin、Mohammed Sharique、Uttam K. Tambar
DOI:10.1021/jacs.9b08801
日期:2019.10.30
new C-C bonds represents a powerful approach to generate complex molecules from simple starting materials. However, a general and controllable method for the sequential conversion of a methyl group into a fully substituted carbon center remains a challenge. We report a new method for the selective and sequential replacement of three C-H bonds at the allylicposition of propylene and other simple terminal
将 CH 键直接转化为新的 CC 键代表了一种从简单的起始材料生成复杂分子的强大方法。然而,将甲基顺序转化为完全取代的碳中心的通用且可控的方法仍然是一个挑战。我们报告了一种新方法,用于选择性和顺序替换丙烯和其他简单末端烯烃的烯丙基位置的三个 CH 键,该烯烃具有源自格氏试剂的不同碳基团。铜催化剂和富电子联芳膦配体有助于以高支链选择性形成烯丙基烷基化产物。我们还提出了在催化铜和手性膦配体存在下生成对映体富集的烯丙基烷基化产物的条件。通过这种方法,