نتایج جستجو برای: phosphines
تعداد نتایج: 579 فیلتر نتایج به سال:
The 1,4-addition of a monofluoromethyl nucleophile to a variety of alpha,beta-unsaturated compounds has been achieved under mild conditions using either phosphines or potassium carbonate at room temperature. alpha-Substituted fluoro(phenylsulfonyl)methane easily undergoes Michael addition to alpha,beta-unsaturated ketones, esters, nitriles, sulfones, as well as propynoates at room temperature t...
Phosphorus-based Mannich-type reactions (phospha-Mannich reactions) of primary or secondary phosphines with carbonyl compounds and amines (R2NH, RNH2, NH3) provide a powerful synthetic tool in the worldwide search for future ligands. The variety available allows designing fine-tuning water-soluble, chiral, macrocyclic, pincer, tripodal, photoactive, etc., phosphine ligands P–C–N linkage(s) (P,N...
We demonstrate that allenes, chiral 1,2-dienes, appended with basic functionality can serve as ligands for transition metals. We describe an allene-containing bisphosphine that, when coordinated to Rh(I), promotes the asymmetric addition of arylboronic acids to α-keto esters with high enantioselectivity. Solution and solid-state structural analysis reveals that one olefin of the allene can coor...
New Pd-NHC complexes have been synthesized and employed for palladium-catalyzed direct arylation of pyrrole derivatives by using electron-deficient aryl chlorides as coupling partners. The desired coupling products were obtained in moderate to good yields by using 1 mol % of these air-stable palladium complexes. This is an advantage compared to the procedures employing air-sensitive phosphines,...
Abstract This invited Team Profile was created by the Gessner and Gooßen research groups at Ruhr-University Bochum (Germany). They recently published a series of articles in Angewandte Chemie on application ylide-substituted phosphines (YPhos) palladium-catalyzed coupling reactions. Owing to their inherently strong sigma-donating ability modular synthesis, YPhos ligands can be tailored fit dema...
Generations 1 to 3 of dendrimers ended by water-soluble phosphines are synthesized and their ruthenium complexes are used as catalysts in aqueous media; a slightly positive dendritic effect on the regioselectivity is observed for hydration of alkynes and a large positive dendritic effect is observed in the biphasic (water/heptane) catalysed isomerisation of allylic alcohols to ketones where the...
Reduction of phosphine oxides into the corresponding phosphines using PhSiH3 as a reducing agent and Ph3C+[B(C6F5)4]? an initiator is described. The process highly efficient, broad range secondary tertiary alkyl arylphosphines, bearing various functional groups in generally good yields. reaction believed to proceed through generation silyl cation, which with oxide provides phosphonium salt, fur...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید