Palladium-Catalyzed Cross-Coupling of Aryl Electrophiles with Dimethylalkynylaluminum Reagents
摘要:
Alkynyldimethylaluminum reagents are easily available from terminal akynes and trimethylaluminum via a triethylamine-catalyzed metalation. These compounds can react with various aromatic and heterocyclic halides in the presence of palladium in a fast and efficient way. This catalyzed cross-coupling reaction provides a simple entry to numerous internal alkynes, using a readily available, inexpensive, and nontoxic metalating agent.
Palladium-Catalyzed Decarboxylative<i>sp</i>-<i>sp</i><sup>2</sup>Cross-Coupling Reactions of Aryl and Vinyl Halides and Triflates with α,β-Ynoic Acids using Silver Oxide
作者:Hyunseok Kim、Phil Ho Lee
DOI:10.1002/adsc.200900502
日期:2009.11
Palladium-catalyzed decarboxylative sp-sp2 cross-couplingreactions of aryl and vinyl halides and triflates with α,β-ynoic acids using silver oxide have been developed. A variety of α,β-ynoic acids were readily decarboxylated in the presence of silver oxide and then, generated in situ, silver acetylides were coupled with electrophiles in the presence of a palladium(0) catalyst under neutral conditions
Palladium-Catalyzed Decarboxylative Coupling of Alkynyl Carboxylic Acids and Aryl Halides
作者:Jeongju Moon、Mihee Jang、Sunwoo Lee
DOI:10.1021/jo802290r
日期:2009.2.6
2-Octynoic acid and phenylpropiolic acid were employed for the palladium-catalyzed decarboxylative coupling reaction and with a variety of arylhalides. The former needed 1,4-bis(diphenylphosphino)butane (dppb) as a ligand and the latter tri-tert-butylphosphine (PtBu3), and both required 2 equiv of tetra-n-butylammonium fluoride (TBAF) for full conversion. These reactions showed high reactivities and
Visible-light induced copper(<scp>i</scp>)-catalysed denitrogenative oxidative coupling of hydrazinylpyridines with terminal alkynes
作者:Vaibhav Pramod Charpe、Aniket A. Hande、Arunachalam Sagadevan、Kuo Chu Hwang
DOI:10.1039/c8gc01180j
日期:——
Visible light mediated copper catalysed denitrogenative oxidative coupling of 2-hydrazinopyridines with terminal alkynes to form 2-(alkyl/arylethynyl) pyridines in the presence of O2 at room temperature is reported with 42 examples. This is the first report on visible light stimulated N2 elimination by an in situ generated copper(II) superoxo/peroxo complex. N2 and water are the only by-products. The
Palladium(0)-Catalyzed Cross-Coupling of Potassium (<i>Z</i>)-2-Chloroalk-1-enyl Trifluoroborates: A Chemo- and Stereoselective Access to (<i>Z</i>)-Chloroolefins and Trisubstituted Alkenes
Original and ambivalent: We describe the preparation of a series of new potassiumtrifluoroborates 1, and the study of their behaviour in a Pd0‐catalyzed cross‐coupling reaction. We found that compounds 1 are endowed with original properties as they behave as nucleophilic cross‐coupling partners chemoselectively, but also as ambivalent synthons. The usefulness of this methodology has been successfully
2-(arylethynyl)pyridines with anilines affords stereoselectively Z-enamine products with excellent regioselectivity. The reaction proceeds with moderate to excellent yields and accommodates a diverse range of functional groups on alkynes (ether, bromo, trifluoromethyl, acetyl, and carbomethoxy) and anilines (ether, bromo, chloro, and carbethoxy). The stereochemistry of the obtained enamines is complementary to that