Organomercury Compounds. XXVII. The Synthesis and Properties of Some Carboxylato- and Carboxy-pyridinylmercurials

1985 ◽  
Vol 38 (3) ◽  
pp. 419 ◽  
Author(s):  
GB Deacon ◽  
GN Stretton
Keyword(s):  
Acetic Acid ◽  
Carboxylic Acid ◽  
Dimethyl Sulfoxide ◽  
Mercuric Acetate ◽  
Major Product ◽  
Aqueous Acetic Acid ◽  
Halide Ions ◽  
Iodide Ions ◽  
Organomercury Compounds

Decarboxylation of mercuric pyridine-2,3-dicarboxylate in hot dimethyl sulfoxide or hexamethylphosphoramide gives a mixture of 2-carboxylatopyridin-3-ylmercury(II) (major product) and 3- carboxylatopyridin-2-ylmercury(II) (minor product). The mixture reacts ( i ) with acidified halide ions ( Cl - or I-) to yield a mixture of the corresponding carboxypyridinyl ( halogeno )mercury(II) derivatives, (ii) with tribromide ions to give the bromo ( carboxypyridinyl )mercury(ii) complexes, 3-bromopyridine-2-carboxylic acid, and 2-bromopyridine-3- carboxylic acid, and (iii) with iodide ions in hot aqueous acetic acid to yield bis (2-carboxypyridin-3-yl)mercury(II) hydrogen triiodomercurate (II). Solutions of the last compound in dimethyl sulfoxide deposit bis (2-carboxypyridin-3-yl)mercury(II). Reaction of pyridine-2,3-dicarboxylate ions with mercuric acetate in boiling aqueous acetic acid at pH 5.0-5.8 gives mercurated acetic acid as the sole organometallic product, and the reported1 decarboxylation yielding 3-carboxylatopyridin-2-ylmercury(II) is not observed.

Organomercury Compounds. XVI. Thermal decomposition reactions of mercuric arenesulphonate dihydrates

1973 ◽  
Vol 26 (3) ◽  
pp. 541 ◽  
Author(s):  
PG Cookson ◽  
GB Deacon
Keyword(s):  
Thermal Decomposition ◽  
Acetic Acid ◽  
Sulphuric Acid ◽  
Mercuric Acetate ◽  
Sodium Salts ◽  
Decomposition Reactions ◽  
Tetraphenylarsonium Chloride ◽  
Organomercury Compounds ◽  
Sulphur Trioxide

Thermal decomposition of the mercuric arenesulphonate dihydrates Hg(03SR)2,- 2H20 (R = C6X5, p-HC6X4, or m-HC6C14; X = C1 or F) at c. 130-240" gave the corresponding diarylmercurials, the polyhalogenobenzenes RH, and sulphur trioxide (or sulphuric acid) in all cases, together with RS03H (R = C6F5 or p-HC6F4), and p-(p-HC6F4S03Hg),C6F4. By contrast, decomposition of Hg(03SR)2,2H20 (R = m-HC6F4 or o-HC6X4) gave the corresponding (-HgC6X4S03-), derivatives, sulphonic acids, polyhalogenobenzenes, and sulphur trioxide in all cases, together with m-HC6F4HgO3S-m-HC6F4 and o-(o-HC~C~~SOJH~),C~C~~. The compounds RHg03SR (R = C6C15, isolated as the monopyridinate, or p-HC6C14) were obtained from decomposition of the appropriate mercuric sulphonates at c. 165'. Identities of (-HgC6X4S03-), derivatives were established mainly by cleavage with triiodide ions in N,N-dimethylformamide giving the salts M(IC6X,S03) (M = Na or S-benzylthiouron- ium), and of (HC6X4S03Hg)2C6X4 derivatives by similar degradation giving 12C6X4 and M(HC6X4S03) (M = Na or Ph4As). Similar degradation of C6C15Hg03SC6C15,py, p-HC6Cl,Hg03S-p-HC6C14, and the known mercurials C6C15HgCl, (p-HC6C14),Hg, and (0-HC6C14),Hg gave the corresponding iodopolychlorobenzenes. The mercurated derivative (-o-H~C,F~SO~-)~ gave (-0-HgCsF4-)3 on thermal decomposition, and crystallization from water yielded ( - o - H ~ C ~ F ~ S ~ ~ - ) , , ~ ~ H ~ ~ , which was converted into (Ph4As)(o-C1HgC6F4S03) by tetraphenylarsonium chloride. The mercuric sulphonates were prepared from mercuric acetate and the appro- priate sulphonic acids in acetic acid (X = C1) or water (X = F). Sulphonic acids, obtained by sulphonation reactions, were characterized as the dihydrates and in some cases sodium salts (polychloro derivatives) or as barium and tetraphenylarsonium salts (tetrafluoro derivatives).

The mechanism of lead tetraacetate decarboxylation. II. 2,3,3-Trimethylbutanoic and Adamantane-2-carboxylic acids

1974 ◽  
Vol 27 (8) ◽  
pp. 1693 ◽  
Author(s):  
ALJ Beckwith ◽  
RT Cross ◽  
GE Gream
Keyword(s):  
Acetic Acid ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Major Product ◽  
Lead Tetraacetate ◽  
Oxidative Decarboxylation ◽  
Catalysed Reaction

Oxidative decarboxylation of 2,3,3-trimethylbutanoic acid with lead tetraacetate in benzene or acetic acid affords mainly 3,3-dimethylbut-2-yl acetate; the major product from the cupric salt catalysed reaction is 3,3-dimethylbut-1-ene. The low yields detected of rearrangement products provide evidence for the intermediacy of organolead and organocopper compounds which decompose by SNi displacement or cyclic cis-elimination. Other reactions discussed are oxidative decarboxylation of adamantane-2-carboxylic acid, deamination of 3,3-dimethylbut-2-ylamine, and thermolysis of bis(2,3,3-trimethylbutanoyl) peroxide and of t-butyl adamantane-2-percarboxylate. A reinterpretation of previous results on the oxidative decarboxylation of exo- and endo-nor- bornane-2-carboxylic acid with lead tetraacetate is presented.

Novel Compound from Flowers of Moringa oleifera Active Against Multi- Drug Resistant Gram-negative Bacilli

2020 ◽  
Vol 20 (1) ◽  
pp. 69-75
Author(s):  
Santi M. Mandal ◽  
Subhanil Chakraborty ◽  
Santanu Sahoo ◽  
Smritikona Pyne ◽  
Samaresh Ghosh ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Moringa Oleifera ◽  
Aqueous Acetic Acid ◽  
Phytochemical Analysis ◽  
Hydroxyl Groups ◽  
Drug Resistant ◽  
Gram Negative ◽  
Isolated Compound ◽  
Conventional Antibiotics

Background: The need for suitable antibacterial agents effective against Multi-drug resistant Gram-negative bacteria is acknowledged globally. The present study was designed to evaluate the possible antibacterial potential of an extracted compound from edible flowers of Moringa oleifera. Methods: Five different solvents were used for preparing dried flower extracts. The most effective extract was subjected to fractionation and further isolation of the active compound with the highest antibacterial effect was obtained using TLC, Column Chromatography and reverse phase- HPLC. Approaches were made for characterization of the isolated compound using FTIR, NMR and Mass spectrometry. Antibacterial activity was evaluated according to the CLSI guidelines. Results: One fraction of aqueous acetic acid extract of M. oleifera flower was found highly effective and more potent than conventional antibiotics of different classes against Multi-drug resistant Gram-negative bacilli (MDR-GNB) when compared. The phytochemical analysis of the isolated compound revealed the presence of hydrogen-bonded amine and hydroxyl groups attributable to unsaturated amides. Conclusion: The present study provided data indicating a potential for use of the flowers extract of M. oleifera in the fight against infections caused by lethal MDR-GNB. Recommendations: Aqueous acetic acid flower extract of M. oleifera is effective, in-vitro, against Gram-negative bacilli. This finding may open a scope in pharmaceutics for the development of new classes of antibiotics.

HSCCC Separation of Three Main Compounds from the Crude Extract of Dracocephalum Tanguticum by Using Dimethyl Sulfoxide as Cosolvent

2020 ◽  
Author(s):  
Xue Yang ◽  
Yongling Liu ◽  
Tao Chen ◽  
Nana Wang ◽  
Hongmei Li ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Ethyl Acetate ◽  
Dimethyl Sulfoxide ◽  
Efficient Method ◽  
Crude Extract ◽  
High Speed ◽  
Glacial Acetic Acid ◽  
Butyl Alcohol ◽  
Preparative Hplc ◽  
Counter Current

Abstract Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate.

The synthesis of norbornanes with functionalized carbon substituents at a bridgehead. 1-(3-Oxonorborn-1-yl)ethanone and 1-(3-oxonorborn-1-yl)-2-propanone

1992 ◽  
Vol 70 (5) ◽  
pp. 1492-1505 ◽  
Author(s):  
Peter Yates ◽  
Magdy Kaldas
Keyword(s):  
Acetic Acid ◽  
Carboxylic Acid ◽  
Hydrogen Bromide ◽  
Tertiary Alcohol ◽  
Ethyl Bromoacetate ◽  
Second Molar ◽  
Molar Equivalent ◽  
Acid Lactone ◽  
Basic Hydrolysis ◽  
Hydrolysis Of

Treatment of 2-norobornene-1-carboxylic acid (7) with one equivalent of methyllithium in ether followed by a second molar equivalent after dilution with tetrahydrofuran gave 1-(norborn-2-en-lyl)ethanone (10) and only a trace of the tertiary alcohol 11. Reaction of 7 with formic acid followed by hydrolysis gave a 4:3 mixture of exo-3- and exo-2-hydroxynorbornane-1-carboxylic acid (16 and 17), whereas oxymercuration–demercuration gave only the exo-3-hydroxy isomer 16. Oxidation of 16 and 17 gave 3- and 2-oxonorbornane-1-carboxylic acid (27 and 29), respectively. Oxymercuration–demercuration of 10 gave exclusively 1-(exo-3-hydroxynorborn-1-yl)ethanone (30), which was also prepared by treatment of 16 with methyllithium in analogous fashion to that used for the conversion of 7 to 10. Oxidation of 30 gave 1-(3-oxonorborn-1-yl)ethanone (1). Dehydrobromination of exo-2-bromonorbornane-1-acetic acid and dehydration of 2-hydroxy-norbornane-2-acetic acid derivatives gave 1-(norborn-2-ylidene) acetic acid derivatives to the exclusion of norborn-2-ene-1 -acetic acid derivatives. Treatment of exo-5-acetyloxy-2-norobornanone (52) with ethyl bromoacetate and zinc gave ethyl exo-5-acetyloxy-2-hydroxynorbornane-(exo- and endo-2-acetate (53 and 54). Reaction of 53 with hydrogen bromide gave initially ethyl endo-3-acetyloxy-exo-6-bromonorbornane-1-acetate (59), which was subsequently converted to a mixture of 59 and its exo-3-acetyloxy epimer 61. Catalytic hydrogenation of this mixture gave a mixture of ethyl endo- and exo-3-acetyloxynorbornane-1 -acetate (62 and 63). Basic hydrolysis of this gave a mixture of the corresponding hydroxy acids, 70 and 71; the former was slowly converted to the latter at pH 5. Oxidation of the mixture of 70 and 71 gave 3-oxonorbornane-1-acetic acid (72). Treatment of the mixture with methyllithium as for 16 gave a mixture of 1-(endo- and exo-3-hydroxynorborn-1-yl)-2-propanone (73 and 74), which was oxidized to 1-(3-oxo-norborn-1-yl)-2-propanone (2). Reaction of exo-2-hydroxynorbornane-1-acetic acid lactone (75) with methyllithium in ether gave (1-(exo-2-hydroxynorborn-1-yl)-2-propanone (76), which on oxidation gave the 2-oxo isomer 78 of 2.

Compatibility studies of chitosan/PVA blend in 2% aqueous acetic acid solution at 30°C

2010 ◽  
Vol 82 (2) ◽  
pp. 251-255 ◽  
Author(s):  
H.M.P. Naveen Kumar ◽  
M.N. Prabhakar ◽  
C. Venkata Prasad ◽  
K. Madhusudhan Rao ◽  
T.V. Ashok Kumar Reddy ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Acid Solution ◽  
Acetic Acid Solution ◽  
Aqueous Acetic Acid ◽  
Compatibility Studies ◽  
Aqueous Acetic Acid Solution

scholarly journals Perborate Oxidation of Substituted 5-Oxoacids in Aqueous Acetic Acid Medium: A Kinetic and Mechanistic Study

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
S. Shree Devi ◽  
B. Muthukumaran ◽  
P. Krishnamoorthy
Keyword(s):  
Acetic Acid ◽  
Acid Medium ◽  
Reaction Rate ◽  
Reaction Medium ◽  
Activation Parameters ◽  
Reaction Rates ◽  
Mechanistic Study ◽  
Aqueous Acetic Acid ◽  
Sodium Perborate ◽  
Acetic Acid Medium

Kinetics and mechanism of oxidation of substituted 5-oxoacids by sodium perborate in aqueous acetic acid medium have been studied. The reaction exhibits first order both in [perborate] and [5-oxoacid] and second order in [H+]. Variation in ionic strength has no effect on the reaction rate, while the reaction rates are enhanced on lowering the dielectric constant of the reaction medium. Electron releasing substituents in the aromatic ring accelerate the reaction rate and electron withdrawing substituents retard the reaction. The order of reactivity among the studied 5-oxoacids is p-methoxy ≫ p-methyl > p-phenyl > –H > p-chloro > p-bromo > m-nitro. The oxidation is faster than H2O2 oxidation. The formation of H2BO3+ is the reactive species of perborate in the acid medium. Activation parameters have been evaluated using Arrhenius and Eyring’s plots. A mechanism consistent with the observed kinetic data has been proposed and discussed. Based on the mechanism a suitable rate law is derived.

Improved synthesis of anti-sesquinorbornene

1984 ◽  
Vol 62 (9) ◽  
pp. 1840-1844 ◽  
Author(s):  
Karl R. Kopecky ◽  
Alan J. Miller
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Carboxylic Acid ◽  
Lead Tetraacetate ◽  
Carboxyl Group ◽  
Silver Acetate ◽  
Benzenesulfonyl Chloride ◽  
Methoxide Ion ◽  
Hydrolysis Of ◽  
Monomethyl Ester

Treatment of methyl hydrogen decahydro-1,4:5,8-exo,endo-dimethanonaphthalene-4a,8a-dicarboxylate with lead tetraacetate in benzene – acetic acid replaces the carboxyl group by an acetoxy group. Hydrolysis of this product with 25% sulfuric acid at 130 °C forms 8a-hydroxydecahydro-1,4:5,8-exo,endo-dimethanonaphthalene-4a-carboxylic acid 10. The reaction between 10 and benzenesulfonyl chloride in pyridine containing triethylamine at 95 °C produces anti-sesquinorbornene 1 in 34% yield. In the absence of triethylamine 1 is converted to the hydrochloride. The iodohydroperoxide of 1 is converted by silver acetate at 0 °C to the diketone in a luminescent reaction. The 1,2-dioxetane could not be isolated. Decahydro-1,4:5,8-exo,exo-dimethanonaphthalene-4a,8a-dicarboxylic anhydride is converted slowly by methoxide ion in methanol at 150 °C to the monomethyl ester which then undergoes demethylation. The isomeric exo,endo anhydride undergoes reaction readily with methoxide ion at 80 °C.

Sign in / Sign up

Export Citation Format

Share Document