114288-97-0Relevant articles and documents
Enantioselective decarboxylative alkylation reactions: Catalyst development, substrate scope, and mechanistic studies
Behenna, Douglas C.,Mohr, Justin T.,Sherden, Nathaniel H.,Marinescu, Smaranda C.,Harned, Andrew M.,Tani, Kousuke,Seto, Masaki,Ma, Sandy,Novak, Zoltan,Krout, Michael R.,McFadden, Ryan M.,Roizen, Jennifer L.,Enquist Jr., John A.,White, David E.,Levine, Samantha R.,Petrova, Krastina V.,Iwashita, Akihiko,Virgil, Scott C.,Stoltz, Brian M.
supporting information; experimental part, p. 14199 - 14223 (2012/02/01)
α-Quaternary ketones are accessed through novel enantioselective alkylations of allyl and propargyl electrophiles by unstabilized prochiral enolate nucleophiles in the presence of palladium complexes with various phosphinooxazoline (PHOX) ligands. Excellent yields and high enantiomeric excesses are obtained from three classes of enolate precursor: enol carbonates, enol silanes, and racemic β-ketoesters. Each of these substrate classes functions with nearly identical efficiency in terms of yield and enantioselectivity. Catalyst discovery and development, the optimization of reaction conditions, the exploration of reaction scope, and applications in target-directed synthesis are reported. Experimental observations suggest that these alkylation reactions occur through an unusual inner-sphere mechanism involving binding of the prochiral enolate nucleophile directly to the palladium center. Sly as a PHOX: The development of an enantioselective decarboxylative palladium-catalyzed allylic alkylation reaction, utilizing phosphinooxazoline ligands, is described. The catalyst is applied to a range of allyl enol carbonate, silyl enol ether, and allyl β-ketoester substrates to provide alkylated ketone products in excellent yield and good ee (see scheme). The utility of these products is demonstrated by their use in several asymmetric syntheses. Mechanistic studies are reported suggesting an unusual inner-sphere mechanism. Copyright
Unexpected nucleophilic behaviour of free-radicals generated from α-iodoketones
De Dobbeleer, Corinne,Pospiil, Jii,De Vleeschouwer, Freija,De Proft, Frank,Marko, Istvan E.
supporting information; experimental part, p. 2142 - 2144 (2009/09/06)
The unexpected nucleophilic reactivity of free-radicals generated from α-iodoketones is reported; two different procedures, either employing tin or the more environmentally acceptable ethylsulfone-based coupling reagent 5c have been developed.
Tandem hydroformylation/aldol addition of silyl enol ethers bearing remote olefinic functionalities
Hollmann, Christoph,Eilbracht, Peter
, p. 1685 - 1692 (2007/10/03)
Rhodium(I) complex catalysed hydroformylation of unsaturated silyl enol ethers leads to products of an intramolecular aldol addition in a one-pot procedure. Thus β,γ- or γ,δ-unsaturated silyl enol ethers undergo tandem hydroformylation/Mukaiyama aldol reaction to form cyclic O-silylated aldol adducts with high selectivity and good yields. (C) 2000 Elsevier Science Ltd.
PREPARATION OF THERMODINAMICALLY STABLE ENOL SILYL ETHERS OF γ,δ-UNSATURATED KETONES BY PALLADIUM-CATALYZED DECARBOXYLATION-ALLYLATION OF ALLYL 2,3-DISUBSTITUTED 3-TRIMETHYLSILOXYACRYLATES
Tsuji, Jiro,Ohashi, Yukihiro,Minami, Ichiro
, p. 2397 - 2398 (2007/10/02)
Allyl 2,3-disubstituted 3-trimethylsiloxyacrylates underwent palladium-catalyzed intramolecular decarboxylation-allylation to afford enol silyl ethers of γ,δ-unsaturated ketones.
