Chemistry of the Podocarpaceae. XVII. Ring-A modifications of O-methylpodocarpic acid

1968 ◽  
Vol 21 (10) ◽  
pp. 2473 ◽  
Author(s):  
CR Bennett ◽  
RC Cambie ◽  
TJ Fullerton
Keyword(s):  
Sulphuric Acid ◽  
Oxidation State ◽  
Tertiary Amine ◽  
Acid Chloride ◽  
Nitrous Acid ◽  
Amine Oxide ◽  
Curtius Reaction ◽  
Hydrolysis Of

Methods for the conversion of 0-methylpodocarpic acid (I) into 12-methoxy-16-norpodocarpa-8,11,13-trien-4-amine (11) have been examined, a Curtius reaction on the acid chloride (IV) followed by hydrolysis of the isocyanate (111) with 85% w/w sulphuric acid affording the highest overall yield (44%). Some "simple deaminations" involving no change in oxidation state, have been investigated as possible routes to alkenes suitable for further modification of the A ring of podocarpio acid. These include nitrous acid deamination, treatment of the N-benzoate (VIII) with phosphorus pentabromide or pentachloride, and pyrolysis of the tertiary amine oxide (VII) or quaternary methylammonium iodide.

Deprotonation de N-oxydes d'amines aliphatiques: schéma réactionnel général et nouvelle synthèse de pyrrolidines

1985 ◽  
Vol 63 (3) ◽  
pp. 725-734 ◽  
Author(s):  
René Beugelmans ◽  
Leïla Benadjila-Iguertsira ◽  
Jacqueline Chastanet ◽  
Guillermo Negron ◽  
Georges Roussi
Keyword(s):  
Tertiary Amine ◽  
Amine Oxide ◽  
Secondary Amines ◽  
Lithium Diisopropylamide ◽  
Efficient Synthesis ◽  
Remarkable Property ◽  
Amine Oxides ◽  
Trimethylamine Oxide ◽  
First Time ◽  
Hydrolysis Of

Amine oxides, 1, 5, 10, 15, 21, 23, when treated by lithium diisopropylamide undergo deprotonation. Monodeprotonation gives rise either to secondary amines and benzaldehyde resulting from the hydrolysis of an intermediate immonium (I) or to hydroxylamines via a Stevens-like rearrangement observed for the first time on an amine oxide. Double deprotonation gives an immonium ylid (Y) which, depending upon the structure of the initial tertiary amine yields either "head to head" piperazines (biradical-like behavior of (DD)) or aziridines. The immonium ylid (Y5) derived from trimethylamine oxide, whose formation and reactivity are reported for the first time, has the remarkable property of undergoing cycloaddition reactions with unactivated olefins, leading to a new and efficient synthesis of various pyrrolidines.

Cellulose organic solvents: V. Conformational aspects of N,N-dimethyl ethanolamine N-oxide in its crystalline and diluted states

1984 ◽  
Vol 62 (1) ◽  
pp. 6-10 ◽  
Author(s):  
E. R. Maia ◽  
A. Péguy ◽  
S. Pérez
Keyword(s):  
Tertiary Amine ◽  
Amine Oxide ◽  
Direct Methods ◽  
Monoclinic Space Group ◽  
Cyclic Form ◽  
Asymmetric Unit ◽  
Ir And Nmr Spectroscopy ◽  
Conformational Investigation ◽  
Intramolecular Hydrogen ◽  
Strong Intramolecular Hydrogen Bond

N,N-Dimethyl ethanolamine N-oxide (DMEAO) belongs to the class of tertiary amine oxide molecules that are good solvents for cellulose, although not being cyclic. Crystallographic investigation shows that anhydrous DMEAO is monoclinic, space group Cc, a = 25.725(9), b = 7.023(4), c = 9.483(5) Å, β = 101.16(10)°, Z = 12. The crystal structure has been solved by direct methods and refined to a final R value of 0.063 for 575 observed reflexions. Three independent molecules are found within the asymmetric unit; one of these displays a pseudo-cyclic form dictated by the occurrence of a strong intramolecular hydrogen bond. Conformational investigation of DMEAO in solution, using ir and nmr spectroscopy shows that this pseudo-cyclic form is more likely to occur in diluted states. These findings are related to the ability of this tertiary amine oxide to act as a good solvent, up to a water content of one water molecule per DMEAO molecule.

The synthesis of Cyclododecane-r-1,c-5,c-9-triamine and r-1,c-5,c-9-Tris(2,3-dimethoxybenzamido)cyclododecane

1975 ◽  
Vol 28 (3) ◽  
pp. 673 ◽  
Author(s):  
DJ Collins ◽  
C Lewis ◽  
JM Swan
Keyword(s):  
Aqueous Solution ◽  
Acid Hydrolysis ◽  
Sulphuric Acid ◽  
Sodium Carbonate ◽  
Sodium Azide ◽  
Room Temperature ◽  
Dimethyl Formamide ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Hydrolysis Of

Treatment of cyclododecane-r-1,c-5,c-9-triyl tris(p-toluenesulphonate) with sodium azide in dimethyl-formamide at 100� for 6 h gave the corresponding cis,cis-triazide which upon hydrogenation or reduction with lithium aluminium hydride gave cyclododecane-r-1,c-5,c-9-triamine, isolated as the tris-salicylidene derivative. Acid hydrolysis of this, removal of the salicylaldehyde, and treatment of the aqueous solution with sodium carbonate and 2,3-dimethoxybenzoyl chloride gave r-1,c-5,c- 9-tris(2,3-dimethoxybenzamido)cyclododecane. ��� Treatment of (E,E,E)-cyclododeca-1,5,9-triene with an excess of acetonitrile and sulphuric acid at room temperature for three days gave 18% of (E,E)-1-acetamidocyclododeca-4,8-diene; no di- or tri-amides were isolated.

scholarly journals Studies on Tertiary Amine Oxide. IX

1961 ◽  
Vol 81 (4) ◽  
pp. 574-578 ◽  
Author(s):  
Masatoxno Hamana ◽  
Motoyoshi Yamazaki
Keyword(s):  
Tertiary Amine ◽  
Amine Oxide

THE CONSTITUTION OF A SYNTHETIC GLUCAN: II. METHYLATION STUDIES

1963 ◽  
Vol 41 (10) ◽  
pp. 2439-2446 ◽  
Author(s):  
G. G. S. Dutton ◽  
A. M. Unrau
Keyword(s):  
Sulphuric Acid ◽  
Hydrolysis Of

After repeated and vigorous treatments, a fully methylated glucan was obtained. Hydrolysis of the methylated glucan with sulphuric acid gave tetra-, tri-, di-, and mono-O-methyl-D-glucoses in a 5:5:3:1 ratio. Both the furanose and pyranose tetramethyl isomers were identified. Nearly all of the possible pyranose and furanose cyclic trimethylglucoses were positively identified. An attempted resolution of the dimethylglucoses was relatively unsuccessful. The monomethylglucoses were identified by electrophoresis.

HYDROLYSIS OF CELLULOSE ACETATE SULPHATE IN ACETONE

1954 ◽  
Vol 32 (9) ◽  
pp. 815-822 ◽  
Author(s):  
Karl Keirstead ◽  
John Myers
Keyword(s):  
Acetic Acid ◽  
Cellulose Acetate ◽  
Sulphuric Acid ◽  
Potentiometric Titration ◽  
Titration Method ◽  
Acetate Ester ◽  
Hydrolysis Of Cellulose ◽  
Potentiometric Titration Method ◽  
Hydrolysis Of

When cellulose acetate sulphate is dissolved in acetone the hydrolysis of the sulphate ester is rapid compared with that of the acetate ester. In 70% acetone the relative rates are reversed. Hydrolysis of the sulphate ester in acetone is greatly affected by the temperature. At 25 °C. or greater the hydrolysis is complete after 24 hr. A potentiometric titration method has been developed for the estimation of sulphuric acid in the presence of smaller amounts of acetic acid.

scholarly journals Complexing power of hydro-soluble degradation products from γirradiated polyvinylchloride: influence on Eu(OH)3(s) solubility and Eu(III) speciation in neutral to alkaline environment

2017 ◽  
Vol 105 (8) ◽  
Author(s):  
Pascal E. Reiller ◽  
Elodie Fromentin ◽  
Muriel Ferry ◽  
Adeline Dannoux-Papin ◽  
Hawa Badji ◽  
...  
Keyword(s):  
Oxidation State ◽  
Alkaline Hydrolysis ◽  
Degradation Products ◽  
Alkaline Environment ◽  
Hydrolysis Of

AbstractThe complexing power of hydrosoluble degradation products (HDPs) from an alkaline hydrolysis of a 10 MGy γ-irradiated polyvinylchloride is studied. The complexation of Eu(III), as an analogue of lanthanide and actinide radionuclides at their +III oxidation state for oxygen containing functions, is evidenced both from the increasing of Eu(OH)

scholarly journals Changes in u(VI) SPeciation Upon Sorption onto Montmorillonite from Aqueous and Organic Solutions

1991 ◽  
Vol 257 ◽  
Author(s):  
Catherine Chisholm-Brause ◽  
Steven D. Conradson ◽  
P. Gary Eller ◽  
David E. Morris
Keyword(s):  
Oxidation State ◽  
Aqueous Systems ◽  
X Ray ◽  
Ph Values ◽  
Uranium Oxidation ◽  
Organic Solutions ◽  
X Ray Absorption ◽  
Hydrolysis Of ◽  
Uranium Species ◽  
Lines Of Evidence

ABSTRACTThe speciation of UO22+ and UO22+/ TBP mixtures has been investigated in solution and intercalated with the reference smectite clay SAz-1 using x-ray absorption, Raman, andluminescence spectroscopies. Neither aquated UO22+ nor its TBP complex undergoes any detectable changes in uranium oxidation state on intercalation. Further, at the pH values employed in this work, there is no evidence for hydrolysis of the uranium species to generate dimeric or higher order uranium oligomers. However, we do find indications that the structures of the solution complexes are altered on intercalation, particularly for the UO22+TBP system and for more dilute UO22+/aqueous systems. In addition, several lines of evidence suggest that, at the loading levels used in this study, the uranyl species is interacting with two or more spectroscopically distinguishable sites on SAz-1.

Hemtacetal formation in sulphuric acid hydrolysis of a chloro olefin

1973 ◽  
Vol 14 (8) ◽  
pp. 585-588 ◽  
Author(s):  
E.P. Woo ◽  
K.T. Mak ◽  
H.N.C. Wong
Keyword(s):  
Acid Hydrolysis ◽  
Sulphuric Acid ◽  
Hydrolysis Of
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