Search results for "direct arylation"
showing 3 items of 3 documents
Diastereoselective Synthesis of Dialkylated Bis(phosphino)ferrocenes: Their Use in Promoting Silver-Mediated Nucleophilic Fluorination of Chloroquino…
2017
International audience; The diastereoselective synthesis of dialkylated ferrocenyl bis(phosphane)s bearing aryl, alkyl, and hetero- or polycyclic substituents on the phosphino groups is reported, together with their characterization in the solid state by X-ray structure analysis and in solution by multinuclear NMR spectroscopy. Introduction of various alkyl groups on the ferrocene backbone, namely, tert-butyl, isopropyl, and trimethylsilyl, has a significant influence on the stereoselectivity of the ensuing lithiation/phosphination reactions. Only the introduction of the tert-butyl groups ensures both a high yield and perfect diastereoselectivity, which leads to the exclusive formation of t…
A Versatile Palladium/Triphosphane System for Direct Arylation of Heteroarenes with Chloroarenes at Low Catalyst Loading
2010
International audience; Put a ring on it: The use of an air-stable, robust palladium/tridentate phosphane catalyst in direct C[BOND]H and C[BOND]Cl activation reactions is reported (see scheme; DMAc=N,N-dimethylacetamide, TBAB=tetra-n-butylammonium bromide). Electron-rich, electron-poor, and polysubstituted furans (X=O), thiophenes (X=S), pyrroles (X=NR5), and thiazoles were arylated with chloroarenes in the presence of the catalyst.
A general diastereoselective synthesis of highly functionalized ferrocenyl ambiphiles enabled on a large scale by electrochemical purification
2017
International audience; A general synthesis of highly functionalized ferrocenes, which include (P,B)- and (N,B)-ambiphiles, has been developed at a multigram scale. Diastereoselective stepwise modification of di-tert-butylated ferrocenes included the unprecedented separation of electroactive species. Bulky alkyl groups on ferrocenes ensure planar chirality of ambiphiles and enforce closer proximity of antagonist Lewis functions.