An improved synthesis of 1,3-dihydro-1-methyl-5-phenyl-2H-pyrido[3,4-e]-1,4-diazepin-2-one via ortho-directed lithiation of 3-tert-butyl and 3-tert-butoxycarbonylaminopyridine

1987 ◽  
Vol 65 (6) ◽  
pp. 1158-1161 ◽  
Author(s):  
Charles Y. Fiakpui ◽  
Edward E. Knaus
Keyword(s):  
Acid Hydrolysis ◽  
Good Yield ◽  
Tert Butyl ◽  
Acid Catalyzed ◽  
Glycine Derivatives

The ortho-directed lithiation of 3-tert-butyl- or 3-tert-butoxycarbonylaminopyridines (3) with alkyllithiums and reaction with N,N-diethylbenzamide followed by acid hydrolysis gave 3-amino-4-benzoylpyridine (6) in good yield. Reaction of BTBO with the glycine derivatives 7a, b and then reaction with 6 afforded 3-alkoxycarbonylaminomethylcarbonylamino-4-benzoylpyridines 8a, b. Acid-catalyzed hydrolysis and cyclization of 8a, b yielded 9, which on methylation gave 1,3-dihydro-1-methyl-5-phenyl-2H-pyrido[3,4-e]-1,4-diazepin-2-one (10) in 36% overall yield from 3a.

The bromination and chlorination of 2,3-dialkylindoles. Isolation of 3-bromo- and 3-chloro-2,3-dialkylindolenines and acid catalyzed conversion to 3-methoxyindolenines

1980 ◽  
Vol 58 (8) ◽  
pp. 808-814 ◽  
Author(s):  
Gary I. Dmitrienko ◽  
Edward A. Gross ◽  
Susan F. Vice
Keyword(s):  
Acetic Acid ◽  
Good Yield ◽  
Room Temperature ◽  
Chemical Properties ◽  
Nitrogen Atmosphere ◽  
Crystalline Solid ◽  
Tert Butyl ◽  
Acidic Conditions ◽  
Acid Catalyzed

The bromination of 2,3-dimethylindole in acetic acid followed by hydrolysis has been shown to yield the known dimer 16 of 3-hydroxy-2,3-dimethylindolenine 15 and not 3-hydroxymethyl-2-methylindole 12 as reported previously by others. Bromination of 2,3-dimethylindole in the presence of triethylamine has yielded 3-bromo-2,3-dimethylindolenine 17 as a crystalline solid which is stable at room temperature in a nitrogen atmosphere in the presence of triethylamine but decomposes vigorously in the absence of base. Under mildly acidic conditions 17 reacts rapidly with methanol to yield 3-methoxy-2,3-dimethylindolenine 3 in good yield. With tert-butyl hypochlorite in the presence of triethylamine, 2,3-dimethylindole gives 3-chloro-2,3-dimethylindolenine 2 which has chemical properties similar to 17 reacting readily with methanol to give 3. Similarly tetrahydrocarbazole was converted to the analogous chloroindolenine 5 and bromoindolenine 18 both of which readily underwent methanolysis to give 6 in good yield. A mechanism for the acid catalyzed methanolysis of 3-chloro- and 3-bromoindolenines is proposed.

Preparation of conjugates of uridine with proteins by the imido ester condensation method

1981 ◽  
Vol 46 (4) ◽  
pp. 933-940 ◽  
Author(s):  
Helmut Pischel ◽  
Antonín Holý ◽  
Günther Wagner
Keyword(s):  
Human Serum ◽  
Acid Hydrolysis ◽  
Ester Hydrochloride ◽  
Protein Conjugates ◽  
Condensation Method ◽  
Ester Condensation ◽  
Acid Catalyzed

Reaction of 5'-O-p-toluenesulfonyl-2',3'-O-isopropylideneuridine (I) with sodium 4-cyanophenoxide afforded 2',3'-O-isopropylidene-5'-O-(4-cyanophenyl)uridine (II) which was converted by acid hydrolysis into 5'-O-(4-cyanophenyl)uridine (IIIa). Acid-catalyzed addition of ethanol to compound IIIa gave the imido ester hydrochloride IIIb which on reaction with ammonia or ethylamine was transformed into the amidine derivatives IIIc and IIId. Compound IIIb reacted with human serum albumine or bovine gamma-globuline at pH 9.2 to give protein conjugates with uridine, bound covalently by an amidine bond (IIIe,f).

ChemInform Abstract: Acid Catalyzed tert-Butylation and Tritylation of 4-Nitro-1,2,3-triazole: Selective Synthesis of 1-Methyl-5-nitro-1,2,3-triazole via 1-tert-Butyl-4-nitro-1,2,3-triazole.

ChemInform ◽  
2013 ◽  
Vol 44 (6) ◽  
pp. no-no
Author(s):  
yuliya V. Filippova ◽  
Anna G. Sukhanova ◽  
Sergei V. Voitekhovich ◽  
Vadim E. Matulis ◽  
Gennady T. Sukhanov ◽  
...  
Keyword(s):  
Selective Synthesis ◽  
Tert Butyl ◽  
Acid Catalyzed

THE ACID HYDROLYSIS OF GLYCOSIDES: I. GENERAL CONDITIONS AND THE EFFECT OF THE NATURE OF THE AGLYCONE

1964 ◽  
Vol 42 (6) ◽  
pp. 1456-1472 ◽  
Author(s):  
T. E. Timell
Keyword(s):  
Acid Hydrolysis ◽  
Equilibrium Concentration ◽  
Rate Coefficients ◽  
Acidity Function ◽  
Tertiary Alcohols ◽  
Conjugate Acid ◽  
Rate Of Hydrolysis ◽  
Acid Catalyzed ◽  
Opposing Effects ◽  
Hydrolysis Of

First-order rate coefficients and energies and entropies of activation have been determined for the acid-catalyzed hydrolysis of a number of methyl D-glycopyranosides and disaccharides. The relation between the logarithm of the rate coefficients and values for Hammett's acidity function was linear, although different for different acids. All compounds had entropies of activation indicating a unimolecular reaction mechanism. Glucosides of tertiary alcohols were hydrolyzed very rapidly, triethylmethyl β-D-glucopyranoside, for example, 30,000 times taster than the corresponding methyl compound.Increase in size of the aglycone caused a slight increase in the rate of hydrolysis of β-D-glucopyranosides, steric hindrance thus being of no significance. Electron-attracting substituents in the aglycone had little or no influence on the rate of hydrolysis, obviously because they would tend to lower the equilibrium concentration of the conjugate acid, while facilitating the subsequent heterolysis, the two opposing effects more or less cancelling out. These results were discussed in connection with recent studies on the acid hydrolysis of various phenyl glycopyranosides and with reference to the postulated occurrence of an activating inductive effect in oligo- and poly-saccharides containing carboxyl or other electronegative groups at C-5. It was concluded that there is little evidence for the existence of any such effect and that, for example, pseudoaldobiouronic acids should be hydrolyzed at the same rate as corresponding neutral disaccharides.

Reduction by Dissolving Metals

1955 ◽  
Vol 8 (4) ◽  
pp. 512 ◽  
Author(s):  
AJ Birch ◽  
J Cymerman-Craig ◽  
M Slaytor
Keyword(s):  
Acid Hydrolysis ◽  
Good Yield ◽  
Liquid Ammonia ◽  
The Right

The reduction by sodium and ethanol, with or without liquid ammonia as solvent, of various amidines followed by acid hydrolysis, leads in many cases to a good yield of the corresponding aldehyde. Further reduction in liquid ammonia of several 2-aryl-imidazolines or imidazolidines followed by acid hydrolysis leads to the 2,5-dihydro-benzaldehyde derivative. The reduction of some acid amides by sodium and proton sources in liquid ammonia has been examined. Under the right conditions this process is of preparative value for aldehydes.

Functionalisation of Imidazolin-2-imine to Corresponding Phosphinamine, Chalcogenide (O, S, Se, Te), and Borane Compounds

2015 ◽  
Vol 68 (1) ◽  
pp. 127 ◽  
Author(s):  
Kishor Naktode ◽  
Sayak Das Gupta ◽  
Abhinanda Kundu ◽  
Salil K. Jana ◽  
Hari Pada Nayek ◽  
...  
Keyword(s):  
Good Yield ◽  
Density Functional ◽  
Elemental Sulfur ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
Tert Butyl ◽  
Imine Ligands ◽  
Orbital Analysis

1,3-Di-tert-butyl-imidazolin-2-ylidine-1,1-diphenylphosphinamine (2) was prepared from 1,3-di-tert-butyl-imidazolin-2-imine (1) and chlorodiphenylphosphine. Compound 2 was treated further with elemental sulfur, selenium, and tellurium to afford the corresponding chalcogenide derivatives, 1,3-di-tert-butyl-imidazolin-2-ylidine-P,P-diphenyl-phosphinothioicamide (4), 1,3-di-tert-butyl-imidazolin-2-ylidine-P,P-diphenyl-phosphinoselenoicamide (5), and 1,3-di-tert-butyl-imidazolin-2-ylidine-P,P-diphenyl-phosphinotelluroicamide (6) in good yield. 1,3-Di-tert-butyl-imidazolin-2-ylidine-P,P-diphenylphosphinicamide (3) was obtained by dissolving compound 2 in hydrochloric acid solution in THF. The corresponding borane adduct, 1,3-di-tert-butyl-imidazolin-2-ylidine-P,P-diphenyl-phosphinaminoborane (7) was isolated by the reaction of compound 2 and sodium borohydride in good yield. The molecular structures of compounds 2 and 4–7 were established by X-ray diffraction analyses. To analyse the electronic structure of chalcogenides of imidazolin-2-imine ligands, the protonation energies of the oxygen, sulfur, and selenide derivative of ligand 2 were calculated by means of density functional theory. Finally, the charge distribution in compounds 3, 4, and 5 were determined using natural bond orbital analysis.

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