Decarboxylative Allylation of Glyoxylic Acids with Diallyl Carbonate
作者:Filipe Manjolinho、Matthias F. Grünberg、Nuria Rodríguez、Lukas J. Gooßen
DOI:10.1002/ejoc.201200766
日期:2012.9
ketones. The key advantage of the new reaction protocol is that preformation of the allyl esters is not required. The reaction is believed to proceed via phosphane-mediated decarboxylation of the α-oxocarboxylates, leading to acyl anionequivalents that are allylated within the coordination sphere of the palladium catalyst. Under the reaction conditions, the double bond then migrates into conjugation
Synthesis of α,β-Unsaturated Ketones by Pd-Catalyzed Decarboxylative Allylation of α-Oxocarboxylates
作者:Nuria Rodríguez、Filipe Manjolinho、Matthias F. Grünberg、Lukas J. Gooßen
DOI:10.1002/chem.201102584
日期:2011.12.2
A palladium/p‐tolylphosphine system has been developed that catalyzes the extrusion of carbon dioxide from α‐oxocarboxylic acid allyl esters, leading to α,β‐unsaturated ketones (see scheme). The palladium complex activates the substrate and mediates the carbon–carbon bond formation to give allyl ketones, and subsequent double bond shift to the α,β position. The actual decarboxylation step with formation
Asymmetricconjugate additions of phosphonates to trans-crotonophenone and chalcone derivatives using a diaminomethylenemalononitrile organocatalyst resulted in the generation of the corresponding chiral γ-ketophosphonates in high yields with excellent enantioselectivities (up to 95% ee). This report is the first successful example of asymmetric 1,4-additions of phosphonate to α,β-unsaturated ketones
Steric and Electronic Requirements in the Synthesis of 2,3-Dihydro-4(1<i>H</i>)-quinolinones by the Tandem Michael-S<sub>N</sub>Ar Reaction
作者:Richard A. Bunce、Takahiro Nago、Suaad Abuskhuna
DOI:10.1002/jhet.2142
日期:2015.7
heterocyclic products in molecules having monoactivated SNAr aromatic acceptor rings (X═H) and very good yields for diactivated systems (X═NO2). For these hindered substrates, success in the final cyclization hinges on the ability of the aromatic acceptor to capture the pendant nitrogen nucleophile of the initial Michael adduct before this intermediate can revert to starting materials.
已经研究了通过串联Michael‐S N Ar反应合成2,3-二氢‐4(1 H)‐喹啉酮的空间和电子要求。在β-烯酮碳上带有单个甲基的底物,从具有X═H或NO 2的E和Z异构体得到的标题化合物均具有出色的收率。与β底物,在迈克尔末端β二甲基取代了的杂环产物的低产率在已经monoactivated小号分子Ñ的Ar芳族受体环(X = H)和非常良好的产率为diactivated系统(X═NO 2)。对于这些受阻的底物,最终环化的成功取决于芳族受体在该中间体可转化为起始原料之前捕获初始迈克尔加合物的侧链氮亲核试剂的能力。