نتایج جستجو برای: allylic alcohols
تعداد نتایج: 13311 فیلتر نتایج به سال:
Efficient asymmetric bio-epoxidation of electron-deficient α,β-unsaturated ketones was realized via a tandem reduction-epoxidation-dehydrogenation cascade, which proceeds in a switchable manner to afford either chiral epoxy ketones or allylic epoxy alcohols with up to >99% yield and >99%ee.
Unsymmetrical ketones and allyltitanocenes generated by the desulfurizative titanation of γ,γ-disubstituted allyl phenyl sulfides react under highly diastereoselective construction of adjacent quaternary stereocenters (see scheme; R(L) = large group, R(S) = small group). The title reaction is stereospecific: the anti- and syn-homoallylic alcohols are obtained by the reaction of E- and Z-allylic...
In the presence of 2.5 mol% Pd2(dba)3-TMEDA (1 : 4), a range of enantioenriched allylic alcohols smoothly coupled with boronic acids in a highly regioselective fashion with inversion of configuration to afford structurally diverse alkenes in good yields with perfect retention of ee.
The palladium hydride-iminium complex generated from Pd/C and triethylamine catalyses the isomerisation of allylic alcohols into carbonyl compounds, and Pd/C catalyses the conjugate reduction of activated double bonds using triethylamine as the source of the two newly incorporated hydrogen atoms via the same complex.
A novel radical phosphinylation of α,α-diaryl allylic alcohols with arylphosphine oxides was described for the direct preparation of α-aryl-β-phosphinylated carbonyl ketones in medium to good yields via 1,2-aryl migration. In this reaction, formation of new C(Ar)-C(sp(3)) and C(sp(3))-P bonds was observed.
This review discusses the tertiary phosphines possessing various chiral skeletons that have been used in asymmetric nucleophilic organocatalytic reactions, including annulations of allenes, alkynes, and Morita-Baylis-Hillman (MBH) acetates, carbonates, and ketenes with activated alkenes and imines, allylic substitutions of MBH acetates and carbonates, Michael additions, γ-umpolung additions, an...
A set of new bis-spirofused 1,2,4-trioxanes 4a-d was obtained from the reaction of cyclohexane-1,4-dione with allylic hydroperoxides 2a-d, bearing an additional hydroxy group in the homoallylic position, by diastereoselective photooxygenation of allylic alcohols 1a-d and subsequent BF(3)-catalyzed peroxyacetalization with the diketone. From the reaction of a monoprotected cyclohexane-1,4-dione ...
The scope of a recently reported method for the catalytic enantioselective bromochlorination of allylic alcohols is expanded to include a specific homoallylic alcohol. Critical factors for optimization of this reaction are highlighted. The utility of the product bromochloride is demonstrated by the first total synthesis of an antibacterial polyhalogenated monoterpene, (-)-anverene.
We have modified Merrifield’s resin to provide polymers containing secondary amine groups. Lithiation of the solids gives strongly basic yet poorly nucleophilic resins useful for rearrangement of epoxides to their corresponding allylic alcohols. The resins are easy to handle, non-volatile, non-toxic, and are easily recovered and reused, providing environmental and economic benefits that might h...
A brief, enantioselective synthesis of a hydroxymethyl-cis-1,3-cyclopentenediol building block is presented. This scaffold allows access to the cis-1,3-cyclopentanediol fragments found in a variety of biologically active natural and non-natural products. This rapid and efficient synthesis is highlighted by the utilization of the palladium-catalyzed enantioselective allylic alkylation of dioxano...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید