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Carbonyl Carbonyldiimidazole

The antiarrhythmic activity of local anesthetics has been noted several times previously. Another such agent is prepared by first alkylating isopropylamine with sulfone 199. Reaction of the ])ioduct (200) with diethylethylenediamine and carbonyldiimidazole results in transfer of the CDI carbonyl group and formation of the urea suricainide (201) [52]. The transform in all likelihood involves stepwise replacement of the imidazole groups by the basic groups in the other reactants. [Pg.49]

Another compound 9 with three heterocyclic rings linearly fused (5 5 5) with two heteroatoms has been prepared from 1,1 -carbonyl diindole 297 <2001T5199>. Palladium-mediated coupling of the 2- and 2 -positions of 297 afforded the 1,1 -carbonyl-2,2 -biindolyl 9. 1,1 -Carbonyl diindole 297 was in turn obtained in 41% yield from 1,1 -carbonyldiimidazole 296 by reaction with indole in DMSO at 125 °C. The palladium-catalyzed coupling step afforded the desired product 9 in low yield and required a stoichiometric amount of palladium acetate. Therefore, it was felt prohibitively expensive. Addition of various co-oxidants (Ac20, Mn02, and Cu(OAc)2, etc) to make the reaction catalytic in palladium did not result in any improvement of the yield of 18 (Scheme 53). [Pg.671]

Reaction of dipyrrinones such as 242 with A,A -carbonyldiimidazole (CDI) have been used to synthesize carbonyl-bridged dipyrrinones such as 243, which are highly fluorescent compounds (Equation 66) <2002JOC2713>. [Pg.739]

Cyclic ureas, —NHC(0)NH—, have been similarly produced using carbonyl chloride, N,N -carbonyldiimidazole, carbon monoxide, thiocarbonyl chloride or carbon disulfide... [Pg.606]

Carbonyldiimidazole does certainly stand out as one of the most remarkable reagents for peptide coupling. Carboxylic acids react readily with this reagent to yield acyl imidazoles which in turn couple with the amino group of a peptide to produce a new acyl-nitrogen linkage with very little racemization. Reaction of the acylimidazolide with other nucleophiles can lead to a variety of carbonyl derivatives (62AG(E)35l). [Pg.463]

Carbonyldiimidazole can also function as a carbonyl equivalent (79TL4517). Condensation of the dianion derived from an a-hydroxy ketone (545) with this reagent provides a general although modest yield approach to tetronic acids (546 equation 7). [Pg.464]

The elimination of water from (3-hydroxy-a-amino acid derivatives 28 is a particularly valuable method for the synthesis of DHAs 29, when the corresponding hydroxy compounds are readily accessible, such as, those of Ser, Thr and Ser( 3-Ph). 93 Some of the reagents recommended for the elimination of water are disuccinimidyl carbonate, 9495 l,l -carbonyl-diimidazole, 96 or a base and acetic anhydride. 97 Reaction of l,l -carbonyldiimidazole with arylidene Ser esters gives the corresponding DHA derivatives. 98 In the, presence of tri-ethylamine with terminally protected Ser and Thr residues in an inert solvent this reagent affords the AAla and AzAbu acid derivatives in good yields 96 (Scheme 10). This is perhaps one of the simplest and cleanest ways to prepare AAla and AAbu derivatives. [Pg.644]

Methyl acetoacetate, 60 p-(Tolylsulfinyl)methyllithium, 115 Intramolecular acylation 1,1 -Carbonyldiimidazole, 66 of organometallic reagents to form carbonyl compounds... [Pg.353]

T-Carbonyldiimidazole, 125 Carbonyl sulfide, 112-113 Cardenolides, 325 Carpanone, 61 Carpesiolin, 158... [Pg.332]

To a solution of 7.5 g thereof, in 300 ml of tetrahydrofuran is added 5 g of l,l -carbonyldiimidazole and the resultant mixture stirred at room temperature for 1 hour. To this mixture is added 5 g of l,3-dihydro-l-(4-piperidyl)-2H-benzimidazol-2-one, and the reaction is heated at reflux temperature for 48 hours. After cooling to room temperature, the reaction mixture is poured into 150 ml of ice-water and extracted into 150 ml of methylene chloride. The organic extracts are washed successively with 150 ml of sodium carbonate solution, 150 ml of water and 150 ml of dilute hydrochloric acid, then dried over magnesium sulfate, filtered, and the solvent is evaporated under reduced pressure to yield l,3-dihydro-l- l-[(4-methyl-4H,6H-pyrrolo[l,2-a][4,l]benzoxazepin-4-yl)carbonyl]-4-piperidinyl -2H-benzimidazol-2-one, m.p. 208°-210°C. [Pg.3502]

AD-mix-P 9-BBN Bn Boc Bz BOM CDI m-CPBA CSA Cy DBU DDQ DEAD DIAD DIBAL-H DIPT DME DMF DMAP DMSO EDC HMPA HOBT KHMDS LDA MEM MOM MoOPH NaHMDS NBS NMM NMO Piv PMB Reagent for Sharpless asymmetric dihydroxylation 9-Borabicyclo[3.3.1 ]nonyl Benzyl t-Butoxy carbonyl Benzoyl B enzyloxy methyl Carbonyldiimidazole m-Chloroperoxybenzoic acid Camphorsulfonic acid Cyclohexyl 1,8 -Diazabicy clo[5.4.0] undec-7-ene 2,3 -Dichloro-5,6-dicyano-p-benzoquinone Diethyl azodicarboxylate Diisopropyl azodicarboxylate Diisobutylaluminum hydride Diisopropyl tartrate Dimethoxyethane A,N-Dimethylformamide 4-Dimethylaminopyridine Dimethyl sulfoxide N-(3-Dimethylaminopropyl)-A -ethylcarbodiimide Hexamethylphosphoramide 1 -Hydroxybenzotriazole Potassium hexamethyldisilazane Lithium diisopropylamide Methoxyethoxymethyl Methoxymethyl Oxidodiperoxymolybdenum(pyridine)(hexamethylphophoramide) Sodium hexamethyldisilazane N - Bromosuccinimide A-Methylmorpholine A-Methylmorpholine A-oxide Pivaloyl /j-Methoxybenzyl... [Pg.199]

Af,Af/-Carbonyldiimidazole (CDI) is a highly reactive carbonylating agent that is used for activation of carboxyl or hydroxyl groups for conjugation to amines... [Pg.71]

When intermediate 81 is formed from indole 80 and l,l -carbonyldiimidazole (GDI) using DMAP to promote indole nitrogen acylation in acetonitrile at reflux, it is reasonably stable, observed by TLC, but not isolated. Treatment of intermediate 81 in situ with amines, alcohols, or thiols afforded the desired derivatives 82. During the reaction of indoles with GDI, some carbonyl diindole 83 was formed. In many cases this material could be isolated and characterized. In an alternative approach, alcohols reacted with GDI stoichiometrically to form an unstable intermediate carbamate species 84, which could in turn be reacted with indoles to form the desired indole-1-carboxylates 82. This new methodology for the formation of compound 82 proved to be useful in one of the approaches for the synthesis of novel Serotonergics. [Pg.58]

Carbon dioxide, 94 Carbon disulfide-Methyl iodide, 94-95 Carbon monoxide, 95 Carbonylation, 95, 146, 393 a-Carbonyl dimethyl acetals, 460 N,N -Carbonyldiimidazole, 85, 96, 242, 243 Carbopenams, 291... [Pg.293]

V.A-Carbonyldiimidazole (CDI) 15 is another reagent to activate carboxylic acids for nucleophilic substitution at the carbonyl group. ... [Pg.240]


See other pages where Carbonyl Carbonyldiimidazole is mentioned: [Pg.138]    [Pg.481]    [Pg.16]    [Pg.219]    [Pg.333]    [Pg.420]    [Pg.114]    [Pg.228]    [Pg.606]    [Pg.946]    [Pg.529]    [Pg.78]    [Pg.1022]    [Pg.267]    [Pg.121]    [Pg.173]    [Pg.175]    [Pg.203]    [Pg.635]    [Pg.198]    [Pg.754]    [Pg.1022]    [Pg.391]   
See also in sourсe #XX -- [ Pg.873 ]




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1,1 -Carbonyldiimidazole

Carbonylation reaction with carbonyldiimidazoles

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