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Coupling reagents

Lithium metal in tetrahydrofuran can also be used as the coupling reagent, and unsymmetrical ditins can be prepared when the reaction is conducted in stages (162,163). [Pg.75]

Seebach and coworkers have developed the rtmldple coupling reagent, 2-tiitro-2-propenyl 2,2-dimethylpropanoate fNPPi. The reaction of nitromethane v/ith formaldehyde gives 1,3-dihydroxy-2-nitropropane in 95% yield. Subsequent acyladon v/ith two eqidviilents of pivaloyl chloride and elimination of pivalic acid affords NPP. The reacdon may be run on a 40- to 200-g... [Pg.41]

DNA synthesizers operate on a principle similar to that of the Merrifield solid-phase peptide synthesizer (Section 26.8). In essence, a protected nucleotide is covalently bonded to a solid support, and one nucleotide at a time is added to the growing chain by the use of a coupling reagent. After the final nucleotide has been added, all the protecting groups are removed and the synthetic DNA is cleaved from the solid support. Five steps are needed ... [Pg.1114]

C2Hs.C02.CH2.CH2,N02 mw 147,15 N 9.52% OB to C02 -114.15% colorl mobile liq mp, when distd above 150° the compd deton bp 106.0 to 108.2° at 10mm d 1.1727g/cc RI 1.4336. Prepn is by reacting at a boil 2-nitro-ethylalcohol with propionic acid in benz solvent, with coned sulfuric acid as the coupling reagent. The prod is recovered by vac distn Ref Beil 2, 524 ... [Pg.954]

Nitrates and nitrites are first reduced to nitrosyl chloride with thionyl chloride. The volatile nitrosyl chloride then reacts with 4-aminobenzenesulfonic acid to yield a diazonium salt that then couples with 8-hydroxyquinoline to form a colored azo compound. Hence, the coupling reagent is applied to the chromatogram first. [Pg.41]

Fig. 6 Commonly used additives and coupling reagents. DCC dicyclohexylcarbodiimide, HOSu A-hydroxysuccinimide, HOBt 1 -hydroxybenzotriazole, HOAt 1 -hydroxy-7-azabenzotriazole... Fig. 6 Commonly used additives and coupling reagents. DCC dicyclohexylcarbodiimide, HOSu A-hydroxysuccinimide, HOBt 1 -hydroxybenzotriazole, HOAt 1 -hydroxy-7-azabenzotriazole...
The cobalt-catalysed reaction between aryl bromides and Grignard reagents assisted by IMes HCl is also known, however the substrate scope is quit narrow and good yields are only obtained when non-branched long chain alkyl magnesium chlorides are used as coupling reagents [80] (Scheme 6 19)... [Pg.168]

The first version of SPPS to be developed used the t-Boc group as the amino-protecting group. f-Boc can be cleaved with relatively mild acidic treatment and TFA is usually used. The original coupling reagents utilized for SPPS were carbodiimides. In addition to dicyclohexylcarbodiimide (DCCI), N, (V -diisopropylcarbodiimide (DIPCDI) is often used. The mechanism of peptide coupling by carbodiimides was... [Pg.1246]

At the present time, the coupling is usually done via an activated ester (see Section 3.4). The coupling reagent and one of several A-hydroxy heterocycles are first allowed to react to form the activated ester, followed by coupling with the depro-tected amino group. The most frequently used compounds are A-hydroxysuccinimide, 1-hydroxybenzotriazole (HOBt), and l-hydroxy-7-azabenzotriazole (HOAt).47... [Pg.1248]

Another family of coupling reagents frequently used with the Fmoc method is related to A-hydroxybenzotriazole and A-hydroxy 7-azabenzotriazole but also incorporates phosphonium or amidinium groups. The latter can exist in either the O-(uronium) or A-(guanidinium) forms.48 Both can effect coupling. The former are more reactive but isomerize to the latter. Which form is present depends on the protocol of preparation, including the amine used and the time before addition of the carboxylic acid 49 The... [Pg.1248]

Scheme 13.77. Phosphonium, Uronium, and Guanidinium Coupling Reagents... Scheme 13.77. Phosphonium, Uronium, and Guanidinium Coupling Reagents...
In the early solution phase syntheses of oligonucleotides, coupling of phosphate diesters was used. A mixed 3 -ester with one aryl substituent, usually o-chlorophenyl, was coupled with a deprotected 5 -OH nucleotide. The coupling reagents were sulfonyl halides, particularly 2,4,6-tri-i-propylbenzenesulfonyl chloride,53 and the reactions proceeded by formation of reactive sulfonate esters. Coupling conditions... [Pg.1250]


See other pages where Coupling reagents is mentioned: [Pg.144]    [Pg.262]    [Pg.73]    [Pg.345]    [Pg.97]    [Pg.31]    [Pg.31]    [Pg.739]    [Pg.430]    [Pg.225]    [Pg.212]    [Pg.221]    [Pg.57]    [Pg.97]    [Pg.100]    [Pg.954]    [Pg.166]    [Pg.142]    [Pg.142]    [Pg.932]    [Pg.41]    [Pg.158]    [Pg.282]    [Pg.55]    [Pg.32]    [Pg.32]    [Pg.440]    [Pg.440]    [Pg.176]    [Pg.199]    [Pg.252]    [Pg.256]    [Pg.1245]    [Pg.1249]   
See also in sourсe #XX -- [ Pg.232 ]




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Alcohols, allylic coupling with Grignard reagents

Aldehydes, coupling reagents

Alkenylzinc reagent coupling

Alkenylzinc reagents cross-coupling

Alkyl iodides cross-coupling with Grignard reagents

Alkynyl Grignard reagents, coupling with

Allyl bromide coupling with Grignard reagent

Allylic barium reagents coupling

Aminium coupling reagents

An Aid to Deciphering the Constitution of Coupling Reagents from Their Abbreviations

Application of Functionalized Magnesium Reagents in Cross-coupling Reactions

Aromatic rings coupling with lithium reagents

Arylzinc halides, coupling reactions organozinc reagents

Arylzinc reagent coupling

C -organozinc reagents cross-coupling reactions

Carbodiimide coupling reagent

Carbodiimides coupling reagents

Carbonylative Coupling Reactions with Organometallic Reagents

Chemical structures coupling reagents

Coupling Gngnard reagent

Coupling Reagents and Methods for Solid-Phase Synthesis

Coupling Reformatsky reagent

Coupling and Introducing Building Block Reagents

Coupling of Grignard reagents

Coupling of organocopper reagents

Coupling of organometallic reagents with

Coupling reactions Grignard reagents/cobalt salts

Coupling reactions Grignard reagents/copper salts

Coupling reactions Grignard reagents/iron salts

Coupling reactions Grignard reagents/palladium complexes

Coupling reactions Organocopper reagents

Coupling reactions of organocuprate reagents

Coupling reactions organoboron reagents

Coupling reactions organomagnesium reagents

Coupling reactions organosilicon reagents

Coupling reactions organotin reagents

Coupling reactions reagents

Coupling reactions with organometallic reagents

Coupling reagent mode

Coupling reagents HBTU)

Coupling reagents PyBOP)

Coupling reagents activation method

Coupling reagents and methods

Coupling reagents hexafluorophosphate

Coupling reagents phosphonium

Coupling reagents, nucleotide

Coupling reagents, nucleotide peptide

Coupling vinyl chlorides with Grignard reagents

Coupling with Reagent Schemes

Coupling with organolithium reagents

Coupling with organometallic reagents

Cross-Coupling reactions, transition-metal-catalyzed Grignard reagents

Cross-coupling reactions alkyl halides with Grignard reagents

Cross-coupling reactions with organometallic reagents

Diene coupling protic H—Y trapping reagents

Ditopic supramolecular coupling reagent

Esters, sulfonate coupling with Grignard reagents

Grignard reagent cross coupling

Grignard reagents Kumada cross-coupling

Grignard reagents aryl coupling with

Grignard reagents coupling

Grignard reagents coupling reaction

Grignard reagents coupling reaction with bromobenzene

Grignard reagents coupling reactions with alkyl halides

Grignard reagents cross-coupling reactions

Grignard reagents, bonding coupling with alkyl halides

HOBt as coupling reagent

Halides coupling with organoboron reagents

Halides, alkyl coupling with Grignard reagents

Homo-coupling reactions of miscellaneous arylmetallic reagents to biaryls

Lawesson’s reagent Eschenmoser coupling reaction

Metal catalyzed coupling Grignard reagents

Methylene bromide, coupling reagent

Methylene chloride, coupling reagent

Methylene chloride, coupling reagent oxide)

Multi-coupling reagents

Multifunctional coupling reagents

Negishi coupling alkenylzinc reagents

Negishi coupling alkylzinc reagents

Negishi coupling arylzinc reagents

New Families of Reagents for the Pinacol Coupling Reaction

Newer Coupling Reagents

Nickel-catalyzed arylation cross-coupling with Grignard reagents

Organo-copper reagents, coupling

Organocopper reagents coupling

Organocopper reagents cross-coupling reactions

Organolithium reagents coupling reactions

Organolithium reagents coupling with alkyl halides

Organosilicon reagents coupling

Organotin reagents coupling

Organotin reagents, in cross-coupling

Organotin reagents, in cross-coupling reactions

Organozinc compounds arylzinc reagent coupling

Organozinc reagents copper-catalyzed cross-coupling reactions

Organozinc reagents coupling reactions with alkenyl halides

Organozinc reagents cross-coupling

Organozinc reagents cross-coupling reactions with alkyl halides

Organozinc reagents transition-metal-catalyzed cross-coupling

Organozinc reagents, Negishi cross-coupling reactions

Other Supported Coupling Reagents

Oxidative coupling reagents

PALLADIUM-CATALYZED COUPLING OF ACID CHLORIDES WITH ORGANOTIN REAGENTS

Palladium-Catalyzed Cross-Coupling with Grignard Reagents

Palladium-Catalyzed Cross-Coupling with Organolithium Reagents

Palladium-catalyzed arylation cross-coupling with Grignard reagents

Palladium-catalyzed arylation cross-coupling with organolithium reagents

Palladium-catalyzed arylation cross-coupling with organozinc reagents

Peptide coupling reagents

Peptide synthesis, coupling reagents

Phosphonium SPPS coupling reagents

Pinacol coupling metal reagents

Polymer-supported reagents coupling

Preparation of Quinolinylzinc Reagents and Subsequent Coupling Reactions

Propargyl bromide, coupling with an organocopper reagent

Reformatsky reagents coupling reactions

SPPS coupling reagents

STEREOSPECIFIC COUPLING WITH VINYLCOPPER REAGENTS

Samarium reagents ketyl-alkene coupling reactions

Samarium reagents pinacolic coupling reactions

Selective cross-coupling of secondary organozinc reagents

Silver Grignard reagent coupling

Solid coupling reagents

The Kumada Reactions Nickel-Catalyzed Cross-Coupling with Grignard Reagents

The Negishi Reaction Palladium-Catalyzed Cross-Coupling with Organozinc Reagents

Titanium reagents, coupling with

Titanium reagents, coupling with aldehydes

Transition metal-catalyzed coupling of organometallic reagents with organic halides and related electrophiles

Transition-Metal-Catalyzed Cross-Coupling Reactions of Organomagnesium Reagents

Transition-Metal-Catalyzed Cross-Coupling Reactions of Organozinc Reagents

Treatment with silane coupling reagent

Uncatalyzed Cross-Coupling Reactions of Organozinc Reagents

Uronium coupling reagents

YAMADA Coupling reagent

Zinc reagents cross-coupling with alkyl halides

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