Gold-Catalyzed Nitrene Transfer to Activated Alkynes: Formation of α,β-Unsaturated Amidines
摘要:
A gold-catalyzed intermolecular nitrene transfer to alkynes was developed for the first time, revealing a new mode of nitrene transfer and providing a novel access to versatile alpha-imino metal carbenes. Various mild nitrene-transfer reagents were examined, and iminopyridium ylides especially those based on 3,5-dichloropyridine proved be highly effective. With activated alkynes such as N-alkynyloxazolidinones as substrates, alpha,beta-unsaturated amidines were formed in mostly good yields.
Regiospecific Hydroamination of Unsymmetrical Electron-Rich and Electron-Poor Alkynes with Anilines Catalyzed by Gold(I) Immobilized in MCM-41
作者:Dayi Liu、Quan Nie、Rongli Zhang、Mingzhong Cai
DOI:10.1002/adsc.201800621
日期:2018.10.18
heterogeneous gold(I)‐catalyzedregiospecifichydroamination of ynamides and propiolic acid derivatives with anilines has been achieved by using a diphenylphosphine‐functionalized MCM‐41‐supported gold (I) complex and AgNTf2 as catalysts under mild conditions, yielding the corresponding (E)‐N‐arylimines and (Z)‐enamines in good to excellent yields with broad substrate scope. The new heterogeneous gold(I) complex
Iron(II)/copper(I)-mediated stereoselective carbozincation of ynamides. One-pot synthesis of α-allyl-tetrasubstituted-enamides
作者:Hugo Lingua、François Vibert、Dominique Mouysset、Didier Siri、Michèle P. Bertrand、Laurence Feray
DOI:10.1016/j.tet.2017.04.065
日期:2017.6
The iron(II) chloride- and copper(I) iodide-mediated carbozincation of a panel of substituted ynamides is described in this article. The reaction is totally regio- and stereoselective. Experiments showed that the reaction mediated with Fe(II) was more substrate dependent than the reaction performed with Cu(I). Interestingly, in the presence of allylbromide, stereoselective carboallylation can be achieved
N-Substitution dependent stereoselectivity switch in palladium catalyzed hydroalkynylation of ynamides: a regio and stereoselective synthesis of ynenamides
作者:Vikas Dwivedi、Madala Hari Babu、Ruchir Kant、Maddi Sridhar Reddy
DOI:10.1039/c5cc06251a
日期:——
A palladium catalysed regioselective hydroalkynylation of ynamides for ynenamides is achieved with an N-substitution dependent stereoselectivity switch.
Intermolecular Addition of Carbon-Centered Radicals to Ynamides. A Regio- and Stereoselective Route to Persubstituted α-Iodo-enamides
作者:Nejib Dwadnia、Hugo Lingua、Dominique Mouysset、Liliane Mimoun、Didier Siri、Michèle P. Bertrand、Laurence Feray
DOI:10.1021/acs.joc.9b03255
日期:2020.3.20
surprisingly, C-C bond formation through "intermolecular" radical addition to internal ynamides has never been reported. Actually, ynamides are excellent acceptors for "electrophilic" carbon-centered radicals. These processes enable the introduction of functionalized alkyl chains at Cβ, groups that have not yet been introduced via the addition of organometallics. Radical carboiodination affords persubstituted