64841-68-5Relevant articles and documents
Palladium-Catalyzed Reactions of Allylic Boronic Esters with Nucleophiles: Novel Umpolung Reactivity
Unsworth, Phillip J.,L?ffler, Lorenz E.,Noble, Adam,Aggarwal, Varinder K.
supporting information, p. 1567 - 1572 (2015/06/30)
Oxidative palladium-catalyzed reaction conditions have been developed to allow for regioselective and stereoselective coupling of allylic boronic esters with a range of carbon-, oxygen-, and nitrogen-based nucleophiles. Studies into the mechanism of the r
Nickel catalysed coupling of allylamines and boronic acid
Trost, Barry M.,Spagnol, Michel D.
, p. 2083 - 2096 (2007/10/02)
Allylamines function as substrates for cross-coupling with boronic acids in the presence of nickel(0) catalysts rather than palladium(0) catalysts.Aryl-, vinyl- and methyl-boronic acids function well.With vinyl derivatives, E-isomers couple more efficiently than Z-isomer and both fully retain the geometrical integrity.Methylations preferably employ the boronic esters like 2-methyl-1,3,2-benzodioxaborole or 2-methyl-1,3,2-dioxaborolane rather than methylboronic acid.The stereochemistry of the reaction involves a net inversion with respect to the allylamine.The regioselectivity is a function of ligand.Generally, sterically bulky donor phosphines promote new C-C bond formation at the less substituted position.Bidentate ligands, notably 1,1'-binaphthyl-2,2'-ylbis(diphenylphosphinite) (BINAPO), promote new C-C bond formation at the more substituted allyl terminus.The amines appear to be the preferred partner compared to allyl alcohols and esters with the boronic acids and give higher stereospecificity.
Asymmetric Allylic Alkylation Catalyzed by Palladium-Sparteine Complexes
Togni, Antonio
, p. 683 - 690 (2007/10/02)
The cationic complex 3-C3H5)(sparteine)>PF6 (6) was found to be a suitable catalyst precursor for the asymmetric alkylation of allylic acetates with Na as the nucleophile.This constitutes one of the first and still rare examples of a phosphine-free system for this type of Pd-catalyzed reaction.Using 5 mol percent of 6, alkylation products were obtained in up to 90 percent isolated yield and 85 percent enantiomeric excess.The alkylation reaction was shown to occur with overall retention of configuration, indicating an analogous mechanism to the one previouslyproposed for phosphine-containing catalysts.The reactivity of allylic acetates is strongly dependent upon the nature of the substituents, open-chain aliphatic substrates being unreactive.