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Addition reaction conjugate

Recent developments focused on the formation of quaternary stereocentres and the use of alternative nucleophilic reagents to organozincs. Mauduit and Alexakis notably reported the highly enantioselective addition of alkyl and aryl Grignard reagents to trisubstituted cyclic enones using l-HPFe (Equation (11.1)).  [Pg.318]

Silylcuprates have been reported to undergo reactions with a number of miscellaneous Michael acceptors [65]. Conjugate addition to 3-carbomethoxy acyl pyri-dinium salts [65a] affords 4-silyl-l,4-dihydropyridines. Oxidation with p-chlorand generates a 4-acyl pyridinium salt that gives the 4-silylnicotinate upon quenching with water, and methyl 4-silyl-2-substituted dihydronicotinates upon quenching with nucleophiles (nucleophilic addition at the 6-position). The stabilized anion formed by conjugate addition to an a, j8-unsaturated sulfone could be trapped intramolecularly by an alkyl chloride [65b]. [Pg.92]

Reagent % yield from 2-cyclohexenone % yield from isophorone % yield from ethyl 2-butynoate (dr) [Pg.93]

3 Reagent employed (0.65 equiv). TMSCI (1.5 equiv). c TMSBr (4 equiv). [Pg.93]


A particular kind of conjugate addition reaction earned the Nobel Prize in chemistry for Otto Diels and Kurt Alder of the University of Kiel (Germany) m 1950 The Diels-Alder reaction is the conjugate addition of an alkene to a diene Using 1 3 buta diene as a typical diene the Diels-Alder reaction may be represented by the general equation... [Pg.409]

Methacryhc acid and its ester derivatives are Ctfjy -unsaturated carbonyl compounds and exhibit the reactivity typical of this class of compounds, ie, Michael and Michael-type conjugate addition reactions and a variety of cycloaddition and related reactions. Although less reactive than the corresponding acrylates as the result of the electron-donating effect and the steric hindrance of the a-methyl group, methacrylates readily undergo a wide variety of reactions and are valuable intermediates in many synthetic procedures. [Pg.246]

Rifamycin S also undergoes conjugate addition reactions to the quinone ring by a variety of nucleophiles including ammonia, primary and secondary amines, mercaptans, carbanions, and enamines giving the C-3 substituted derivatives (38) of rifamycin SV (117,120,121). Many of the derivatives show excellent antibacterial properties (109,118,122,123). The 3-cycHc amino derivatives of rifamycin SV also inhibit the polymerase of RNA tumor vimses (123,124). [Pg.498]

The mechanism of the Fiesselmann reaction between methylthioglycolate and a,P-acetylenic esters proceeds via consecutive base-catalyzed 1,4-conjugate addition reactions to form thioacetal Enolate formation, as a result of treatment with a stronger base, causes a Dieckmann condensation to occur providing ketone 8. Elimination of methylthioglycolate and tautomerization driven by aromaticity provides the 3-hydroxy thiophene dicarboxylate 9. [Pg.185]

Unsaturated chiral oxazolines have been employed in conjugate addition reactions... [Pg.240]

Asymmetric syntheses of heterocycles by conjugate addition reactions 98EJO2051. [Pg.213]

Chiral Cu(ll)-complexes ofbis-oxazolines as Lewis acids for catalyzed cycloaddition, carbonyl addition, and conjugate addition reactions 99PAC1407. [Pg.253]

Quite a number of asymmetric thiol conjugate addition reactions are known [84], but previous examples of enantioselective thiol conjugate additions were based on the activation of thiol nucleophiles by use of chiral base catalysts such as amino alcohols [85], the lithium thiolate complex of amino bisether [86], and a lanthanide tris(binaphthoxide) [87]. No examples have been reported for the enantioselective thiol conjugate additions through the activation of acceptors by the aid of chiral Lewis acid catalysts. We therefore focussed on the potential of J ,J -DBFOX/ Ph aqua complex catalysts as highly tolerant chiral Lewis acid catalyst in thiol conjugate addition reactions. [Pg.285]

With the success in Lewis acid-catalyzed thiol conjugate addition reactions mentioned above, we further tried to apply the J ,J -DBFOX/Ph-nickel(II) aqua complex catalyst to the catalyzed asymmetric conjugate addition reactions of hydroxyl-amines [88, 89]. However, after some preliminary examinations, we found that... [Pg.288]

The l ,J -DBFOX/Ph-transition metal aqua complex catalysts should be suitable for the further applications to conjugate addition reactions of carbon nucleophiles [90-92]. What we challenged is the double activation method as a new methodology of catalyzed asymmetric reactions. Therein donor and acceptor molecules are both activated by achiral Lewis amines and chiral Lewis acids, respectively the chiral Lewis acid catalysts used in this reaction are J ,J -DBFOX/Ph-transition metal aqua complexes. [Pg.291]

Conjugate addition reactions of acyclic Midiael acceptors possessing betetoatom-SLibstituted stereogenic centers in tlieir )>-positions may provide usefiil levels of diastereoselectivity. A typical example is given witli tlie y-alkoxy-substituted enoate 49 in Sdieme 6.8 [17]. High levels of diastereoselectivity in favor of tlie anii addition product SO were found in tlie course of dlmediylcuprate addition. [Pg.192]

Tliis result fits witli tlie notion tliat addition of dilorotrimetliylsilane dianges tlie rate and selectivity-detetcnining step of tlie conjugate addition reaction [22, 42]. [Pg.199]

Copper-catalyzed Enantioselective Conjugate Addition Reactions of Organozinc Reagents... [Pg.224]

A result equivalent to an allylic substitution reaction with a chiral leaving group can also be achieved by a two-step procedure involving a conjugate addition reaction and a subsequent elimination reaction, as demonstrated by Tamura et al., wbo studied the reaction shown in Scheme 8.15 [27]. [Pg.271]


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1,4-Addition reaction (conjugated kinetic control

1,4-Addition reaction (conjugated thermodynamic control

3-Penten-2-one conjugate addition reactions

A-Nitrile anions conjugate addition reactions

Addition reactions conjugated unsaturated carbonyl

Addition reactions diene conjugation

Addition reactions of conjugated dienes

Addition reactions to conjugated dienes

Addition reactions, of conjugated diene

Addition to Conjugated Enynes and Related Reactions

Aldehyde conjugate addition reactions

Aldol-type reactions tandem conjugate addition

Alkaloid conjugate addition reaction

Alkylation by conjugate addition reactions

Allylic anions 1,4-addition reaction with conjugated enones

Allylic carbanions 1,4-addition reaction with conjugated enones

Alpha carbon conjugate addition reactions

Asymmetric conjugate addition-aldol reactions

Asymmetric organocatalysis conjugate addition reactions

Benzoic acid, dihydrodianions conjugate addition reactions

Carbanions conjugate addition reactions

Carbon nucleophiles conjugate addition reactions

Chlorotrimethylsilane conjugate addition reactions

Cinchona-promoted asymmetric conjugate addition reactions

Condensation reactions, carbonyl compounds conjugate addition

Conjugate Addition The Michael Reaction

Conjugate Addition of Heteroatom Nucleophiles and Subsequent Nef Reaction

Conjugate Carbonyl Additions The Michael Reaction

Conjugate addition Michael-type reactions

Conjugate addition Ramberg-Backlund reaction

Conjugate addition cross-coupling reactions

Conjugate addition natural products, cascade reactions

Conjugate addition nucleophiles, aldol reactions

Conjugate addition reactions Alumina

Conjugate addition reactions Camphor

Conjugate addition reactions Lithium diallylcuprate

Conjugate addition reactions Lithium dimethylcuprate

Conjugate addition reactions Methyl acrylate

Conjugate addition reactions Methyl vinyl ketone

Conjugate addition reactions Potassium /-butoxide

Conjugate addition reactions Robinson annulation reaction

Conjugate addition reactions Titanium chloride

Conjugate addition reactions activated alkenes

Conjugate addition reactions alkenylmetals

Conjugate addition reactions asymmetric

Conjugate addition reactions catalyst

Conjugate addition reactions chiral Bronsted bases

Conjugate addition reactions chiral catalysts

Conjugate addition reactions compounds

Conjugate addition reactions condensation

Conjugate addition reactions enamine activation

Conjugate addition reactions enantioselective

Conjugate addition reactions heteroatom-based

Conjugate addition reactions hydrides

Conjugate addition reactions hydroformylation

Conjugate addition reactions hydrogen bonding

Conjugate addition reactions iminium activation

Conjugate addition reactions kinetic conditions for

Conjugate addition reactions lithium amides

Conjugate addition reactions lithium enolate synthesis

Conjugate addition reactions nucleophiles

Conjugate addition reactions of Grignard reagents

Conjugate addition reactions of lithium diorganocopper reagents

Conjugate addition reactions of organocopper reagents

Conjugate addition reactions organocuprates

Conjugate addition reactions organolithium reagents

Conjugate addition reactions organometallic reagents

Conjugate addition reactions phase-transfer catalysis

Conjugate addition reactions stereoselectivity

Conjugate addition reactions with organocopper reagents

Conjugate addition reactions zinc enolates

Conjugate addition, copper-catalyzed reactions

Conjugate addition, copper-catalyzed reactions Grignard reagents

Conjugate addition-aldol reaction

Conjugate carbonyl addition reaction

Conjugate nucleophilic addition reaction

Conjugate nucleophilic addition reaction mechanism

Conjugate reaction

Conjugated addition reaction

Conjugated addition reaction

Conjugated addition/amination reaction

Conjugated compounds addition reactions

Conjugated diene 1,2-addition reactions

Conjugated diene electrophilic addition reactions

Conjugated diene, 1,2-addition electrocyclic reactions

Conjugated diene, 1,2-addition reaction with

Conjugated dienes addition reactions

Conjugated reaction

Conjugative reactions

Copper conjugate addition reactions

Copper-catalyzed Enantioselective Conjugate Addition Reactions of Organozinc Reagents

Directed Conjugate Addition Reactions

Electrophilic addition reactions of conjugated dienes

Enamines conjugate addition reactions

Enantioselective Cascade Reactions Initiated by Conjugate Addition

Enantioselective Conjugate Addition Reactions Proceeding via Other Types of Activation

Enantioselective Conjugate Addition Reactions via Enamine Activation

Enantioselective Conjugate Addition Reactions via Hydrogen-bonding Activation

Enantioselective Conjugate Addition Reactions via Phase-transfer Catalysis

Enantioselective Nickel(n)-Catalysed Conjugate Addition Reactions

Enantioselective nickel-catalysed conjugate addition reactions

Enantioselective reactions (continued conjugate addition

Enantioselective reactions conjugate addition, free radical

Enone , conjugate carbonyl addition reactions

Enone, conjugate carbonyl addition Michael reactions

Enone, conjugate carbonyl addition from aldol reaction

Enone, conjugate carbonyl addition reaction with amines

Enone. conjugate addition reaction with

Enone. conjugate addition reaction with from aldehydes

Enone. conjugate addition reaction with from ketones

Enone. conjugate addition reaction with stability

Enone. conjugate addition reaction with synthesis

Enones conjugate addition reactions

Enones prochiral. conjugate addition reactions

Esters conjugate addition reactions

Esters in conjugate addition reactions

Facial Selectivity in Conjugate Addition Reactions

Frontier orbitals and conjugate addition reactions

Glycine, reactions conjugate addition

Grignard reagents conjugate addition reactions

Ketone conjugate addition reactions

Ketones (Cont conjugate addition reactions

Metal insertion conjugate addition reactions

Metal-mediated conjugate addition reactions

Michael addition Conjugate substitution reaction

Michael reaction Conjugate addition

Nickel or palladium catalysed conjugate addition and other carbozincation reactions

Nitroalkenes conjugate addition reactions

Nucleophilic reactions conjugate additions, sulfur/selenium

Organocopper reagent, conjugate carbonyl addition reactions

Other Conjugate Addition Reactions

P conjugate addition reactions

Reaction Initiated by Conjugate Addition

Reactions asymmetric conjugated addition

Silanes conjugate addition reactions

Silyl enol ethers conjugate addition reactions

Silyl ketene acetals conjugate addition reactions

Stereoselectivity copper conjugate addition reactions

Sultams, N-enoyladdition reactions conjugate additions

Tandem conjugate addition-aldol reactions

Tandem reactions asymmetric conjugate addition

Tandem reactions conjugate addition-Dieckmann

The Conjugate Addition Reaction a Very Convenient Platform for Asymmetric Organocatalysis

Theoretically Based Conjugate Addition Reaction Pathway

Typical Conjugate 1,4-Addition Reaction

Unsaturated aldehyde, conjugate addition reactions

Unsaturated ketone, conjugate addition reactions

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