Studies on the Lignin of Eucalyptus regnans. III. The Isolation of an Alkali Lignin from Sulphate Pulping

1949 ◽  
Vol 2 (1) ◽  
pp. 117
Author(s):  
JWT Merewether
Keyword(s):  
Acetic Anhydride ◽  
Alkaline Hydrolysis ◽  
Empirical Formula ◽  
Benzoyl Chloride ◽  
Dimethyl Sulphate ◽  
Hydroxyl Groups ◽  
Equivalent Weight ◽  
Eucalyptus Regnans ◽  
Alkali Lignin ◽  
Hydrolysis Of

An alkali lignin containing no sulphur has been obtained as a by-product from the sulphate pulping of Eucalyptus regnans. Like other alkali lignins it contains hydroxyl groups, both acidic and alcoholic, as well as methoxyl groups. Acetic anhydride in pyridine yields an octoacetyl derivative which is readily hydrolysed by boiling water to a heptacetyl derivative. In pyridine, benzoyl chloride yields an octobenzoyl derivative while in aqueous alkali it yields a hexabenzoyl compound. Dimethyl sulphate yields a heptamethyl alkali lignin, diazomethane a hexamethyl derivative, while cold alkaline hydrolysis of the latter gives a pentamethyl derivative, and hot alkaline hydrolysis yields an anhydrotrimethyl alkali lignin. One of the methoxyl groups formed by methylation is unstable to acetylation by acetic anhydride in pyridine, heptamethyl alkali lignin yielding a hexamethyldiacetyl derivative, hexamethyl alkali lignin a pentamethyltriacetyl derivative, pentamethyl alkali lignin a tetramethyltetracetyl derivative, and anhydrotrimethyl alkali lignin the corresponding anhydrodimethyltetracetyl alkali lignin. Triphenylchloromethane in pyridine yields a monotrityl derivative.p-Nitrophenylhydrazine gives a di-p-nitrophenylhydrazone and phenylhydrazine a phenylhydrazone-osazone. Potentiometric titration shows two points of inflection and an equivalent weight of 863. The data are consistent with the empirical formula C92Hl04O34(1754) or C73H54O9,(OCH3)14,(OH)3,C(OH),CO-CH20H,C0,COOH

Studies on the Lignin of Eucalyptus regnans. IV. Alkali Lignin

1949 ◽  
Vol 2 (4) ◽  
pp. 600
Author(s):  
JWT Merewether
Keyword(s):  
Empirical Formula ◽  
Black Liquor ◽  
Hydroxyl Groups ◽  
Eucalyptus Regnans ◽  
Alkali Lignin ◽  
Active Methylene ◽  
Methylene Group ◽  
Alcoholic Hydroxyl ◽  
Soluble Alkali

By pulping Eucalyptus regnans using the soda process and acidifying the black liquor a crude alkali lignin has been isolated. This has been separated into two fractions, dioxan-ether insoluble alkali lignin-A and dioxan-ether soluble alkali lignin-B. A series of derivatives has been made from each. The data for alkali lignin-A are consistent with the empirical formula C68H78O27, containing nine methoxyl. groups, three acidic, and four alcoholic hydroxyl groups, one of which is tertiary, one carbonyl, and one active methylene group. Alkali lignin-B has been found to be identical with the alkali lignin previously isolated from sulphate black liquor.

Studies on the Lignin of Eucalyptus regnans F. Muell. V. Ethanol Lignin

1953 ◽  
Vol 6 (1) ◽  
pp. 44
Author(s):  
JWT Merewether
Keyword(s):  
Molecular Weight ◽  
Acetic Anhydride ◽  
Hydrogen Chloride ◽  
Benzoyl Chloride ◽  
Aqueous Alkali ◽  
Carbonyl Groups ◽  
Equivalent Weight ◽  
Eucalyptus Regnans

Lignin has been isolated from Eucalyptus regnans F. Muell. by refluxing with ethanolic hydrogen chloride, and the product separated into an ether-insoluble ethanol lignin-A and an ether-soluble ethanol lignin-B. Ethanol lignin-A has an equivalent weight of 1400 and, on the assumption that the molecular weight is of this order, contains two ethoxyl and nine methoxyl groups. Acetic anhydride and benzoyl chloride in pyridine yield respectively a hepta-acetate and heptabenzoate, while benzoyl chloride in aqueous alkali yields a pentabenzoate. Diazomethane yields a dimethyl derivative which gives a penta-acetate on acetylation. Schotten-Baumann benzoylation of this dimethyl derivative yields a dibenzoate. Two carbonyl groups are present, as shorn by the formation of a bisphenylhydrazone and a bis-p-nitrophenylhydrazone. The data are consistent with the formula C59H38O10(OC2H5)2(OCH3)9(OH)7.

Studies on the lignin of Eucalyptus regnans F. Muell. VII. The acid hydrolysis of ethanyol lignin-A

1953 ◽  
Vol 6 (2) ◽  
pp. 156 ◽  
Author(s):  
JWT Merewether
Keyword(s):  
Hydrochloric Acid ◽  
Acid Hydrolysis ◽  
Carbonyl Group ◽  
Dilute Hydrochloric Acid ◽  
Hydroxyl Groups ◽  
Eucalyptus Regnans ◽  
Ethoxyl Group ◽  
Hydrolysis Of

Ethanol lignin-A from the ethanolysis of Eucalyptus regnans P. Muell. has been hydrolysed with dilute hydrochloric acid with the object of ascertaining whether the combined ethoxyl is present as an acetal or as ether. Hydrolysis with 12 per cent. hydrochloric acid was found to split off one ethoxyl group, while hydrolysis with 20 per cent. acid brought about complete de-ethylation. The de-ethylated ethanol lignin-A contained one carbonyl group less and two hydroxyl groups more than the original ethanol lignin-A. These results lend no support to the hypothesis that alcohol lignins are acetals, and favour the theory that the combined alkoxyl is probably present as ether.

Studies on the Lignin of Eucalyptus regnans I. Thiolignin

1948 ◽  
Vol 1 (1) ◽  
pp. 112
Author(s):  
FN Lahey ◽  
JWT Merewether
Keyword(s):  
Acetic Anhydride ◽  
Pure State ◽  
Dimethyl Sulphate ◽  
Black Liquor ◽  
Eucalyptus Regnans ◽  
Kraft Process

By pulping Eucalyptus regnans by the kraft process, acidifying the black liquor, and fractionating the product, a thiolignin has been prepared in a pure state. Thiolignin reacts with diazomethane to yield a trimethyl derivative, and with dimethyl sulphate to yield a hexamethyl derivative. Thiolignin, trimethylthiolignin, and hexamethylthiolignin react with acetic anhydride in pyridine to yield respectively hepta-, tetra-, and mono-acetyl derivatives. The data obtained are consistent with the formula C52H35O10.(OCH3)9.C(CH3)OH.(CHOH)3.CH = C(OH).OH.SH.

Synthesis of 5-Phenylcytosine Nucleoside Derivatives

1996 ◽  
Vol 61 (4) ◽  
pp. 645-655 ◽  
Author(s):  
Marcela Krečmerová ◽  
Hubert Hřebabecký ◽  
Antonín Holý
Keyword(s):  
Acetic Anhydride ◽  
Thionyl Chloride ◽  
Alkaline Hydrolysis ◽  
Hydrogen Bromide ◽  
Analogous Reaction ◽  
Final Reaction Product ◽  
Cyclic Sulfite ◽  
Higher Temperature ◽  
Hydrolysis Of ◽  
Tin Tetrachloride

Reaction of silylated 5-phenylcytosine with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribose, catalyzed with tin tetrachloride, and subsequent methanolysis afforded 5-phenylcytidine (2). This compound reacted with thionyl chloride in acetonitrile to give cyclic sulfite 3 which on heating in dimethylformamide was converted into 2,2'-anhydro-1-(β-D-arabinofuranosyl)-5-phenylcytosine (4). Analogous reaction of compound 2 with thionyl chloride at reflux gave 5'-chloro-5'-deoxy-2',3'-cyclic sulfite 5. Its heating in dimethylformamide afforded 5'-chloro-2,2'-anhydro derivative 6, mild alkaline hydrolysis led to 5'-chloro-5'-deoxy-5-phenylcytidine (7). Alkaline hydrolysis of 5-phenyl-2,2'-anhydrocytidine (4) gave 5-phenylcytosine arabinoside 8, whereas the 2,2'-anhydro derivative 6 afforded 1-(5-chloro-5-deoxy-β-D-arabinofuranosyl)-5-phenylcytosine (11). At higher temperature, the final reaction product was 2,5'-anhydro-5-phenylcytidine (12). 5'-Chloro-5'-deoxynucleosides 7 and 11 reacted with tri-n-butyl- stannane to give 5'-deoxyribofuranosyl and 5'-deoxyarabinofuranosyl derivatives 15 and 16. 5-Phenylcytidine (2) was converted into the N4-acetate 17 with acetic anhydride. Further reaction with acetic anhydride and hydrogen bromide in acetic acid afforded a mixture of peracetylated 2'-bromo and 3'-bromo derivatives 18 and 19. Reaction with Zn/Cu couple gave 5'-O-acetyl-5-phenyl-2',3'-didehydro derivative 20 and 2',3',5'-tri-O-acetyl-5-phenylcytidine (21). Compound 20 was deblocked to 1-(2,3-dideoxy-β-D-glycero-pent-2-enofuranosyl)-5-phenylcytosine (22). Catalytic hydrogenation of compound 20 over palladium and subsequent deblocking of the protected 2',3'-dideoxy derivative 23 gave 1-(2,3-dideoxy-β-D-glycero-pentofuranosyl)-5-phenylcytosine (24).

Studies on the Lignin of Eucalyptus regnans. II. The Nature of the Hydroxyl Groups and the Presence of the Carbonyl Group in Thiolignin

1948 ◽  
Vol 1 (2) ◽  
pp. 241
Author(s):  
JWT Merewether
Keyword(s):  
Benzoyl Chloride ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Carbonyl Groups ◽  
Eucalyptus Regnans ◽  
Trimethyl Ether ◽  
Free Hydroxyl ◽  
Active Methylene ◽  
Methylene Group ◽  
Alcoholic Hydroxyl

E. regnans thiolignin reacts with p-toluenesulphonyl chloride in pyridine to form a hexatosyl derivative ; its trimethyl ether reacts likewise to form a tritosyl derivative. Both compounds still have a free hydroxyl group which can be acetylated. Similarly they yield a hexabenzoate and tribenzoate respectively by the Schotten-Baumann reaction, but in pyridine, thiolignin reacts with benzoyl chloride to give a heptabenzoate and trimethylthiolignin a tetrabenzoate. No reaction takes place when trimethyl thiolignin is treated with triphenylchloromethane in pyridine. The above data are interpreted as evidence that of the four alcoholic hydroxyl groups three are secondary and one tertiary. With phenylhydrazine, thiolignin yields a phenylosazone ; with p-nitrophenylhydrazine it yields a p-nitrophenylhydrazone. On the other hand, trimethylthiolignin does not react with phenylhydrazine, indicating the absence of non-enolizable carbonyl groups. Thiolignin condenses with benzaldehydes indicating the presence of an active methylene group. From this evidence it is deduced that the grouping CH2-CO-CHOH- is present.

Synthesis and Reactions of Furo[3,2-b]pyrrole Type Aldehydes

1993 ◽  
Vol 58 (9) ◽  
pp. 2139-2149 ◽  
Author(s):  
Alžbeta Krutošíková ◽  
Miloslava Dandárová ◽  
Juraj Alföldi
Keyword(s):  
Acetic Anhydride ◽  
Ammonium Chloride ◽  
Alkaline Hydrolysis ◽  
Sodium Azide ◽  
Nmr Spectra ◽  
Hydrolysis Of ◽  
C Nmr

The synthesis of ethyl 2-formyl-4-benzylfuro[3,2-b]pyrrole-5-carboxylate (I) is described. A series of furo[3,2-b]pyrrole-2-carbaldehyde 2,6-dialkylphenylhydrazones (IIa - IIg) and dimethylhydrazones (IIIa - IIId) were prepared. By reaction of title compounds with hydroxylammonium chloride in acetic anhydride in the presence of pyridine corresponding cyano-substituted compounds (IVa - IVd) were obtained. Alkaline hydrolysis of IVa - IVd gave Va - Vb and the reaction with sodium azide and ammonium chloride in dimethylformamide led to VIa - VId. the structure of the compounds have been proved by UV, IR, 1H and 13C NMR spectra.

THE STRUCTURE AND RESISTANCE TO METHYLATION OF 1,2-β-GLUCANS FROM SPECIES OF AGROBACTERIA

1961 ◽  
Vol 39 (5) ◽  
pp. 1067-1073 ◽  
Author(s):  
P. A. J. Gorin ◽  
J. F. T. Spencer ◽  
D. W. S. Westlake
Keyword(s):  
Plant Pathogens ◽  
Dimethyl Sulphate ◽  
Linear Structure ◽  
Extracellular Polysaccharides ◽  
Dimethyl Formamide ◽  
Hydroxyl Groups ◽  
Partial Acid Hydrolysis ◽  
Sodium Borohydride Reduction ◽  
Chain Lengths ◽  
Hydrolysis Of

The structures of extracellular polysaccharides produced by the plant pathogens Agrobacterium tumefaciens (2 strains), A. rhizogenes, A. radiobacter, A. ruhi, A. gypsophilae, and A. pseudotsugae were investigated. Polymeric material was formed in good yield from all organisms except A. gypsophilae. Periodate oxidations of the polysaccharides and their sodium borohydride reduction products indicated linear 1,2-glucopyranose structures for A. tumefaciens (2 strains), A. rhizogenes, A. radiobacter, and A. rubi polymers. Optical rotational considerations led to the assignment of β-configurations. The linear structure for the A. radiobacter polysaccharide was confirmed by the isolation, after partial acid hydrolysis, of five 1,2-linked oligosaccharides with chain lengths of two to six. Periodate and chromatographic data indicated that the polysaccharide from A. pseudotsugae contained glucose and galactose and 1,6- as well as 1,2-glycopyranose links. It is noteworthy that the polysaccharides from the genus Agrobacteriurm are shown to be mainly 1,2-β-glucans, a structure not yet found in other genera.Treatment of linear 1,2-β-glucans from A. tumefaciens, A. radiobacter, and A. rhizogenes with sodium hydroxide – dimethyl sulphate, followed by silver oxide in methyl iodide dimethyl formamide, did not cause full methylation. Some of the 3-hydroxyl groups were not substituted and possible reasons for this unreactivity are discussed.

The Course of Autoöxidation Reactions in Polyisoprene and Allied Compounds. III. The Oxidation of Rubber in the Presence of Acetic Acid or Acetic Anhydride

1944 ◽  
Vol 17 (2) ◽  
pp. 267-276
Author(s):  
George F. Bloomfield
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Chain Scission ◽  
Considerable Proportion ◽  
Hydroxyl Groups ◽  
Carbonyl Groups ◽  
Free Hydroxyl ◽  
Hydrolysis Of ◽  
Oxygenated Products ◽  
Oxidative Attack

Abstract Oxidation of rubber by oxygen in the presence of acetic anhydride leads to formation of highly oxygenated products containing a considerable proportion of acetoxyl groups. The residual unsaturation of the products of highest acetoxyl content, taken in conjunction with other analytical characteristics, indicates that three, rather than two, acetoxyl groups normally combine with each isoprene unit attacked. Although the bulk of the oxygen introduced is present in the form of acetoxyl groups, a portion occurs as carboxyl and carbonyl groups; also, whenever acetic acid is used (partly or wholly) in place of acetic anhydride, some free hydroxyl groups appear in the oxidized rubber. The proportions of carboxyl and carbonyl groups observed can be correlated satisfactorily with the extent of chain-scission occurring during the oxidation, the groups in question forming the new ends of the severed molecules. Hydrolysis of the acetylated products yields hydroxy acids, which readily undergo lactonic elimination of water. Acetic anhydride and acetic acid can clearly act as auxiliary reagents in autoöxidation reactions, and the detailed results obtained with rubber can be best accounted for on the basis of α-methylene peroxidation, followed by decay reactions involving incorporation of the auxiliary reagent as well as oxidative attack at the double bonds of the rubber.

Synthesis of Novel 4-Amino-5-(disubstituted amino)-2-phenyl-2H-pyridazin-3-ones

1997 ◽  
Vol 62 (5) ◽  
pp. 800-808 ◽  
Author(s):  
Václav Konečný ◽  
Jozefína Žúžiová ◽  
Štefan Kováč ◽  
Tibor Liptaj
Keyword(s):  
Acetic Anhydride ◽  
Alkaline Hydrolysis ◽  
Acetyl Chloride ◽  
Cyclic Amines ◽  
Hydrolysis Of

Substituted 4-amino-2-phenyl-2H-pyridazin-3-ones 5a-5j have been prepared from 4-amino-5-chloro-2-phenyl-2H-pyridazin-3-one 1 which on reactions with acetyl chloride or acetic anhydride gives 4-acetylamino derivative 2 or 4-diacetylamino derivative 3, respectively. Derivatives 2 and 3 with dialkylamines and cyclic amines yielded appropriate 4-acetylamino-5-(disubstituted amino)-2-phenyl-2H-pyridazin-3-ones 4a-4j. Subsequent alkaline hydrolysis of the acetylamino derivatives 4a-4j let to the title compounds 5a-5j, which were screened for pesticidal activity, but none of them reached activity of the used standards.

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