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Synthesis cyclization

As can be seen in the scheme below, the catalytic activity of gold species was also shown in a multi-substituted furan synthesis. Cyclization of allenones in the presence of Au(III)-porphyrin gave rise to the corresponding substituted furan in good to high yields. The catalyst can be recycled several times and still maintain the same catalytic activity <06OL325>. [Pg.186]

Fischer indole synthesis Cyclization of arylhydrazones by heating with an acid or Lewis acid catalyst yields an indole system. The most commonly used catalyst is ZnCl2- The disadvantage of this reaction is that unsymmetrical ketones give mixtures of indoles if R also has an a-methylene group. [Pg.169]

Gutknecht pyrazine synthesis. Cyclization of a-amino ketones produced by reduction of isoni-troso ketones the dihydropyrazines formed are dehydrogenated with Hg20 or CuS04, or sometimes with atmospheric oxygen. [Pg.626]

W A L L A C H Imidazole Synthesis Cyclization of N-alkylamides with PCIs to imidazoles. [Pg.397]

Mannich-type cyclizations of vinylsilanes have found considerable application in the area of alkaloid total synthesis. Cyclizations that occur in the exocyclic mode with respect to the vinylsilane nucleophile have been widely employed to assemble 3-alkylidenepiperidine substructures with high stereocontrol. Overman and coworkers have made extensive use of the acid-promoted conversion of bicyclic oxazolidines to alkylideneindolizidines in their total syntheses of pumiliotoxin A alkaloids (Scheme 36). - " - An illustration of the mild nature of iminium ion-vinylsilane cyclizations is provided in the conversion of (101) to (102), the penultimate precursor of (-i-)-pumiliotoxin A. This conversion was accomplished in 71% yield by heating (101) at 80 C in a methanolic pyridine-pyridinium tosylate buffer (pH 4.5). More strongly acidic conditions had to be avoided since they led to competitive solvolysis of the allylic benzyl ether functionality of the pumiliotoxin A side chain. To the limits of detection by high... [Pg.1030]

ROBINSON - FOULOS Quinoline synthesis Cyclization of 2 ammo styrene derivatives to quinolines... [Pg.165]

Transition-metal-catalyzed intramolecular cycloisomerization is one of the most useful carbocyclization reactions, and specifically, the Rh-catalyzed cycloisomerization of 1,6-enynes provides a powerful tool in organic synthesis. Cyclization of l,6-en5me 452 catalyzed by Wilkinson s catalyst gave 1-exo-methylene-2-cyclohexene 453 via a 6-exo-trig mode in 83% yield (Scheme 2-50). Terminal substitution on the alkene moiety dramatically suppressed the cyclization, and substitution of the terminal alkyne moiety was detrimental to the reaction as well. [Pg.262]

In alkaloid synthesis, cyclization strategies have been mediated by (TMS)3SiH. An example is given by the total synthesis of (—)-slaframine starting from a phenylseleno derivative (eq 31). ... [Pg.751]

Recifeiolide synthesis (cyclization reaction based on a nucleophilic attack of a jr-allyl Pd intermediate). [Pg.110]

A similar approach was used by Sinay (Scheme 6) for a new synthesis of Kdo glycosides and disaccharides [8]. The mannose derived hydroxyheptenitol 30 was converted into the exo-enol ether 31 through a multistep synthesis. Cyclization was achieved using potassium t-butoxide and iodine at low temperature to give the dis-accharidic derivative 32 as the only product of the reaction. The transformation of the iodomethyl appendage into the carboxylic group required a difficult nucleo-... [Pg.204]


See other pages where Synthesis cyclization is mentioned: [Pg.342]    [Pg.848]    [Pg.420]    [Pg.38]    [Pg.277]    [Pg.420]    [Pg.171]    [Pg.4039]    [Pg.665]    [Pg.290]    [Pg.405]    [Pg.23]    [Pg.399]   
See also in sourсe #XX -- [ Pg.58 ]

See also in sourсe #XX -- [ Pg.58 ]

See also in sourсe #XX -- [ Pg.58 ]




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Aldol cyclization in -spatol synthesis

Aldol-type cyclization reaction synthesis

Alkaloid syntheses cyclization reactions

Asymmetric synthesis Nazarov cyclization

Azulenone, hydroaldol cyclization synthesis

Benzocyclobutenecarboxylic acid synthesis via benzyne cyclization

Bergman cyclization, enediyne synthesis

Biomimetic Total Synthesis of Terpenes and Steroids through Polyene Cyclization

Carbohydrates synthesis via radical cyclization

Cyclization 2,3-diphenylindone synthesis

Cyclization 6-methoxy-8-nitroquinoline synthesis

Cyclization Borsche cinnoline synthesis

Cyclization Cadogan-Sundberg indole synthesis

Cyclization alkaloid synthesis

Cyclization cyclobutane synthesis

Cyclization cycloheptane synthesis

Cyclization cyclohexane synthesis

Cyclization cyclononane synthesis

Cyclization cyclooctane synthesis

Cyclization cyclopentane synthesis

Cyclization cyclopropane synthesis

Cyclization indole synthesis

Cyclization l,5-dimethyl-2-pyrrolidone synthesis

Cyclization malonic ester synthesis of cyclobutane

Cyclization natural products synthesis

Cyclization oxetanocin A synthesis

Cyclization pyrazolone synthesis

Cyclization quinoline synthesis

Cyclization reaction in cadinane synthesis

Cyclization reaction in elemane synthesis

Cyclization reaction in germacrane synthesis

Cyclization reactions cyclopentenone synthesis

Cyclization reactions lactone synthesis

Cyclization tryptamine synthesis

Cyclization upon quinolines. Synthesis of calothrixin

Cyclizations C-glycoside synthesis

Cyclizations aziridine synthesis

Cyclizations carba-sugar synthesis

Cyclizations in alkaloid synthesis

Cyclizations of nitrogen radicals in pyrrolidine synthesis

Cyclizations pancratistatin synthesis

Cyclizations synthesis

Cyclizations synthesis

Cycloaddition reactions natural products synthesis, cyclizations

Cyclopentane, synthesis via radical cyclization

Cyclopentanes natural products synthesis, cyclizations

Dienes, cyclization synthesis

Domino cyclization natural products synthesis

Double cyclization synthesis

Enamide cyclizations in alkaloid synthesis

Enamide cyclizations, application in alkaloid synthesis

Enamides cyclization in alkaloid synthesis

Enantioselective synthesis polyene cyclization

Endo cyclization natural products synthesis

Erythramine synthesis via azomethine ylide cyclization

Free radical cyclization synthesis

Hantzschs Synthesis and Related Cyclizations

Indanones synthesis via Nazarov cyclization

Intramolecular Keto Ester Cyclizations Synthesis of Cyclanones

Intramolecular aldol cyclization in -upial synthesis

Intramolecular aldol cyclization in poitediol synthesis

Intramolecular cyclization synthesis

Isoxazolidines synthesis via nitrone cyclization

Isoxazolines synthesis via nitrile oxide cyclization

Lactam synthesis carbonylation, intramolecular cyclization

Lactone synthesis intramolecular cyclization

Locorenine synthesis via azomethine ylide cyclization

Maytansine synthesis via nitrile oxide cyclization

Natural product synthesis 3 + 2] cyclizations

Natural product synthesis carbon nucleophile cyclization

Natural product synthesis oxygen nucleophile cyclization

Natural product synthesis, ring structures 3 + 2] cyclization

Natural product synthesis, ring structures 3 + 2] cyclizations

Nitrogen ylide cyclizations synthesis

Organic synthesis cyclization

Organic synthesis cyclization/cycloaddition reactions

Palladium-Catalyzed Indole Ring Synthesis Oxidative Cyclization

Photochemical cyclizations, precursor synthesis

Pictet-Spengler cyclization synthesis

Pisiferic acid synthesis enone cyclization

Polyene Cyclizations and Polycyclic Synthesis

Radical Cyclizations in Alkaloid Synthesis

Radical cyclization Fukuyama indole synthesis

Radical cyclization azepine synthesis

Reductive cyclization Baeyer-Jackson indole synthesis

Reductive cyclization Leimgruber-Batcho indole synthesis

Reductive cyclization Reissert indole synthesis

Reductive cyclization solid-phase synthesis

Ruthenium-catalyzed synthesis cyclization with alkynes

SYNTHESIS Photochemical cyclization

SYNTHESIS Pschorr cyclization

Solid synthesis cyclization

Solid-Phase Synthesis of 1,3,4-Oxadiazoles and 1,3,4-Thiadiazoles via Selective Cyclization

Squalenoids synthesis via exo alkene cyclization

Synthesis by Halohydrin Cyclizations and Related Reactions

Synthesis of Permethric Acid via Cyclizing 1,3-Dehydrohalogenation

Synthesis of alkaloids Enamide cyclizations for

Synthesis of pyrrolidines by nitrogen radical cyclization

Synthesis with cyclization on the phosphorus

Tether-directed Radical Cyclization Approaches to the Synthesis of C-Glycosides

Tetrahydropyrans synthesis cyclization strategies

Transannular cyclization natural product synthesis

Trehazolin synthesis cyclization

Williamson ether synthesis cyclization reactions

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