HCl In Acetone Research Articles

Trace Enrichment and Atomic Absorption Spectrometric Determination of Lead, Copper, Cadmium and Nickel in Drinking Water Samples by Use of an Activated Carbon Column

A simple method for atomic absorption spectrometric determination of lead, copper, cadmium and nickel in drinking water samples after preconcentration by sorbing 1-(2-pyridylazo) 2-naphthol (PAN) complex of these metals on an activated carbon column has been established. The metal/PAN complexes were quantitatively retained on the activated carbon in the pH range 6-8. Metals retained on the activated carbon column were completely eluted with 2M HCl in acetone. This method was applied to the determination of lead, copper, cadmium and nickel in drinking water samples and good results were obtained (Recoveries >95%, relative standard deviations <7%, relative error <3%).

Column Preconcentration of Trace Amounts of Copper on Activated Carbon from Natural Water Samples

Abstract A method has been established for enrichment of trace amounts of copper in aqueous solutions on an activated carbon column. Copper was quantitatively retained on a chromatographic column packed with activated carbon, after complexation with 1-nitroso-2-naphthol or hexamethylene dithiocarbamate and elution with 2 M HCl in acetone. The developed method was used for the determination of trace amounts of copper in water samples with good results. (Recoveries between 95-101%, relative standard deviations 3-5%)

Carbon-carbon bond activation via formal β-methyl-elimination from [ η5-6,6-dimethylcyclohexadienyl)Ru(DPPE)(CH 2Cl 2)]PF 6

Carbon-carbon bond activation has been observed through a formal β-methyl elimination from a 6,6-dimethylcyclohexadienyl (dmCh) ligand. Reflux of an EtOH solution of RuCl 3 · 3H 2O, (dmCh)H (15 equiv.), and Zn dust (15 equiv.) afforded (dmCh) 2Ru ( 1, 65–77%). Protonation of 1 with HBF 4 · Et 2O in either provided [(dmCh) 2RuH][BF 4] ( 2) in 77% yield; NMR spectra were consistent with either a terminal hydride or rapidly equilibrated agostic ground-state structure. Addition of CH 3CN to 2, or protonation of 1 in CH 3CN, gave [( η 5-dmCh)Ru(NCCH 3) 3][BF 4] ( 3, 70%). Treatment of 3 with 2.0 equiv. PMe 3 or 1.0 equiv. dppe produced [(dmCh)RuL 2(NCCH 3)][BF 4] ( 4, L = PMe 3; 5, L = dppe), which were poor precursors to halide derivatives. Treatment of 1 with 12 M aqueous HCl in acetone generated [(dmCh)RuCl] n ( 6) in 55% yield. Addition of excess norbornadiene to 6 in hexane yielded (dmCh)Ru(NBD)Cl ( 7, 90%), which proved to be a ready precursor to (dmCh)RuL 2Cl ( 8, L = PMe 3, 90%; 9, L 2 = dppe, 53%) upon addition of the appropriate phosphine. Chloride abstraction from 8 with TlPF 6 afforded numerous [(dmCh)Ru(PMe 3) 2(solvent)]PF 6 [( 10-solvent), solvent = CD 2Cl 2, CD 3NO 2, THF, 2-Me-THF] derivatives, but β-methyl elimination was not observed in subsequent thermolyses. A similar chloride abstraction from 9 produced [(dmCh)Ru(dppe)(CD 2Cl 2)]PF 6 ([ 11-CD 2Cl 2]PF 6); thermolysis of 11-CD 2Cl 2 at 91°C for 12 h generated [( η 6-C 7H 8)Ru(dppe)(CH 3)]PF 6 ( 12), presumably via the coordinatively unsaturated precursor, [(dmCh)Ru(dppe)]PF 6 ([ 11]PF 6). The molecularity of the β-methyl elimination pathway remained elusive. Addition of 1.0 equiv. of [Cp 2Fe][PF 6] to 1 in CD 3CN gave 3-PF 6, while oxidation in CD 2Cl 2 provided [(dmCh)Ru( η 6-toluene)]PF 6 ( 13-PF 6); cyclic voltammetry pinpointed the irreversible oxidation at ±0.85 V vs Ag/AgCl in THF. Three critical factors are responsible for β-methyl elimination from [ 11]PF 6: (1) coordinative/electronic unsaturation; (2) the compatability of ruthenium to both dmCh (precursor) and toluene (product) ligation; (3) an orbital with directionality appropriate to accept the migrating methyl group.

Development of methods to monitor exposure to 1-nitropyrene.

On the basis of 32P-postlabeling analysis, treatment of rats with 1-nitropyrene (1-NP) resulted in the formation of multiple DNA adducts in the liver, mammary glands, and peripheral lymphocytes. The one adduct resulting from nitroreduction, N-(deoxyguanosin-8-yl)-1-aminopyrene, constitutes only a minor component among the adducts. In the present study, incubation of calf thymus DNA with mutagenic ring-oxidized metabolites of 1-NP in vitro in the presence and absence of xanthine oxidase also resulted in the formation of multiple adducts. On the basis of their chromatographic behavior, it appears that DNA adducts derived from such metabolites may have been formed in vivo; however, this needs to be confirmed. [3H]1-NP was given to male and female F344 rats and Sprague-Dawley rats by gavage at five dose levels in the range of 0.1 to 1000 micrograms/kg bw. This led to stable hemoglobin adducts accounting for 0.08 +/- 0.05% of the dose (n = 3 rats). The radioactivity associated with hemoglobin following administration of [3H]1-NP was cleared with a half-life of about 14 days, which is faster than that of unmodified erythrocytes in the rat (t1/2 = 30 days). Treatment of the hemoglobin with 1% HCl in acetone, to precipitate the globin, released the radioactivity; it was all bound to the heme moiety. The structures of the heme adducts have not been elucidated; yet, because of their stability, they may be useful as dosimeters for human exposure to 1-NP.(ABSTRACT TRUNCATED AT 250 WORDS)

Investigation of the product from the reactions of ortho-palladized complexes with HCl in acetone by x-ray crystallographic analysis

The reaction of the ortho-palladized complexes of 4,6-diphenyl-5-phenoxy-1,3-dihydropyrimidin-2one with HCI in acetone was studied. The composition and the crystal structure of the single crystals isolated as a result of the synthesis were determined by x-ray crystallographic analysis. The crystals of [C19H17N202]r are triclinic with a = 13.086(6), b = 13.184(9), c = 17.460(12) A, a = 109.73(4), of # = 107.59(4), "/= 99.62(5) ~ V = 2578(3) A s, space group P[, Z --2. The island-type structure consists of centrosymmetric dimeric anions [Pd2Cle] 2(Pd---Clterm 2.27, Pd--Clbrld~e 2.32 1/~, Pd--Pd 3.42 A, ClbPdClb angle 85.0*), the cations of 4,6-diphenyl-5-phenoxy-l,3-dihydropyrimidin2-one C19H17N202, and acetone molecules. In the cations all the phenyl and heterocyclic rings a~e planar. The cations and anions are arranged in layers.

Thiolate complexes of osmium(III) and osmium(IV). Crystal structures of [Os(SC6F5)2(O2CPh)(PMe2Ph)2] and [OsCl-(SC6F5)3(PMe2Ph)

Treatment of [Os(SR)3(PMe2Ph)2](R = C6F5 or C6HF4) with PhCO2H or with HCl in acetone gives, respectively, the red paramagnetic osmium(III) derivatives [Os(SR)2(O2CPh)(PMe2Ph)2]1 and the green, five-co-ordinate, diamagnetic osmium(IV) complexes [OsCl(SR)3(PMe2Ph)]2. X-Ray crystallography has shown that 1(R = C6F5) has an octahedral structure with trans-thiolates, cis-phosphines and a chelating benzoate ligand and that 2(R = C6F5) has a trigonal-bipyramidal structure with thiolates in the equatorial plane.

Purification and characterization of spore-specific catalase-2 from Bacillus subtilis.

Catalase-2, the catalase found in spores of Bacillus subtilis, has been purified to homogeneity from a nonsporulating strain. The apparent native molecular weight is 504,000. The enzyme appears to be composed of six identical protomers with a molecular weight of 81,000 each. The amino acid composition is similar to the composition of other catalases. Like most catalases, catalase-2 exhibits a broad pH optimum from pH 4 to pH 12 and is sensitive to cyanide, azide, thiol reagents, and amino triazole. The apparent Km for H2O2 is 78 mM. The enzyme exhibits extreme stability, losing activity only slowly at 93 degrees C and remaining active in 1% SDS-7 M urea. The green-colored enzyme exhibits a spectrum like heme d with a Soret absorption at 403 nm and a molar absorptivity consistent with one heme per subunit. The heme cannot be extracted with acetone-HCl or ether, suggesting that it is covalently bound to the protein.

Synthesis of a Putative c-Type Cytochrome by Intact, Isolated Pea Chloroplast

In addition to chlorophyll-protein complexes, other proteins were labeled when isolated developing pea (Pisum sativum L.) chloroplasts were incubated with [(14)C]-5-aminolevulinic acid. The major labeled band (M(r) = 43 kilodaltons by lithium dodecyl sulfate-polyacrylamide gel electrophoresis) was labeled even in the presence of chloramphenicol. Heme-dependent peroxidase activity (as detected by the tetramethyl benzidine-H(2)O(2) stain) was not visibly associated with this band. The radioactive band was stable to heat, 5% HCl in acetone, and was absent if the incubation with [(14)C]-5-aminolevulinic acid was carried out in the presence of N-methyl protoporphyrin IX dimethyl ester (a specific inhibitor of ferrochelatase). Organic solvent extraction procedures for the enrichment of cytochrome f from chloroplast membranes also extracted this unknown labeled product. It was concluded that this labeled product was probably a c-type cytochrome; however, the possibility that it might be a protein containing a covalently linked linear tetrapyrrole was not ruled out.

Mössbauer spectroscopy studies on the complex formation of H2PtCl6 and SnCl2 in acetone solution

Complex formation of H2PtCl6 and SnCl2 in the presence of HCl in acetone has been studied quantitatively by using Mossbauer spectroscopy. It has been revealed that Pt(IV) is rapidly reduced by Sn(II) to Pt(II) and with time the product complex [PtCl2(SnCl3)2]n− transforms into a compound with Pt∶Sn=1∶1 ratio that, in turn, transforms to metallic platinum and Sn(IV). In these conditions no formation of stable Pt(O) clusters was observed.

Intramolecular reactions involving positions C(2), C(6) and (C2), C(7) in the bicyclo[3.3.1]nonane ring system

Reactions likely to involve C(2)–C(6) and C(2)–C(7) intramolecular reactions in bicyclo[3.3.1]nonane derivatives are discussed in terms of the conformations available to the ring system. While endo-6-hydroxybicyclo[3.3.1]-nonan-2-one (11) incorporated three deuterium atoms (excluding the hydroxy-group) on heating with NaOD, the exo-isomer (17) exchanged the six hydrogens adjacent to the oxygenation functions but not the carbinyl proton. Evidence is presented favouring a stereospecific base-induced 2,6-hydride migration, most probably proceeding via a twin-twist boat transition state. Treatment of 6,6-ethylenedioxy-2-methoxymethylenebicyclo-[3.3.1]nonane (36) with aqueous HCl in acetone produced 2-hydroxyprotoadamantan-10-one (38) in high yield. This process resulted from hydrolysis of the oxygenated groups thereby liberating the endo-keto-aldehyde intermediate (37) which underwent subsequent intramolecular aldol condensation between the C(2) aldehyde and C(7).

Protoheme extraction from plant tissue

A method for reproducibly estimating the protoheme content of plant tissues has been developed. The tissue sample is homogenized in 80% acetone to remove pigments and lipids; protoheme is then extracted from the tissue residue with 2% HCl in acetone and quantitatively transferred into diethyl ether. After evaporation of the ether, the residue is dissolved in alkaline pyridine, and the protoheme concentration is estimated from a dithionite-reduced-minus-ferricyanide-oxidized spectrum. When compared to some other methods, this procedure gives consistently higher yields.

Ruthenium complexes containing Group 5B donor ligands. Part 3. Rearrangement reactions of some ruthenium(II) carbonyl and thiocarbonyl triphenylphosphine complexes

Reaction of [RuCl2(PPh3)3] with [Ru(CO)Cl2(dmf)(PPh3)2] in acetone (1: 1 molar ratio)(dmf =NN-dimethylformamide) gives a high yield of [(Ph3P)2ClRuCl3Ru(CO)(PPh3)2]·2Me2CO, supporting the mechanism proposed earlier for formation of the analogous thiocarbonyl complex. Extensions of this type of coupling reaction to form [(Ph3P)2BrRuBrCl2Ru(CO)(PPh3),]·Me2CO and [(Ph3P)2ClRuBr2ClRu(CO)(PPh3)2]·Me2CO are also described. Recrystallisation of [Ru(CO)Cl2(dmf)(PPh3)2] from MaOH–CH2Cl2 gives [Ru(CO)Cl2(HOMe)(PPh3)2](4), and prolonged refluxing of the latter in dichloromethane–light petroleum (b.p. 60–80 °C) produces displacement of a PPh3 group with formation of an isomeric mixture of [(Ph3P)Cl(OC)RuCl3Ru(CO)(PPh3)2](5). The same isomeric mixture, together with [{Ru(CO)Cl2(PPh3)2}2], is also formed by reaction of PPh3 with [PPh3(CH2Ph)][Ru(C7H8)(CO)Cl3](2 : 1 molar ratio). Treatment of (5) with Na[BPh4] and PPh3 in CH2Cl2 gives a high yield of [(Ph3P)2(OC)RuCl3Ru(CO)(PPh3)2][BPh4](6). This cation is also formed, together with (5), by prolonged shaking of (4) in ethanol, whereas treatment of (4) with [AsPh4]Cl·HCl in acetone gives [AsPh4][Ru(CO)Cl3(PPh3)2]·Me2CO (7). Related complexes are described, starting from [Ru(CS)Cl2(dmf)(PPh3)2]. Finally, all this information is used to suggest detailed rearrangement mechanisms in the [RuCl2(PPh3)3]–CS2, [PPh3(CH2Ph)][Ru(C7H8)(CO)Cl3]–2PPh3, and the closely related [RuX2(PR3)n]–[Ru2X3(PR3)6]X (X = Cl or Br; n= 3 or 4) systems.

ChemInform Abstract: NEW THIOCARBONYL COMPLEXES OF RUTHENIUM

AbstractUntersuchungen der bekannten Reaktion des Ru(II)‐Komplexes (I) mit CS2 zeigen, daß neben dem Dimeren (II) und dem kationischen Komplex (IV) die diamagnetische Tri‐u‐chlorodiruthenium(II)‐Verbindung (III) entsteht, die analytisch, NMR‐ spektroskopisch und durch Röntgenstruktur‐Untersuchungen charakterisiert wird und ähnliche physikochemische Eigenschaften wie (II) besitzt.

ChemInform Abstract: (BICYCLO(2,2,1)HEPTA‐2,5‐DIENE)CARBONYLTRIHALOGENORUTHENATE(II) COMPLEXES

AbstractDie Halogenspaltung der Ru phosphonium‐ oder Cs‐chlorid in ‐Komplexe (II) durch Reaktion mit Benzyltriphenyl‐ Gegenwart von konzentrierter HCl in entgastem Aceton liefert erstmalig "einen anionischen Ru(II)‐dien‐Komplex (Ia), dem aufgrund von NMR‐Untersuchungen cis‐Struktur zugeordnet wird.

New thiocarbonyl complexes of ruthenium

Reaction of the complex [RuCl2(CS)(PPh3)2]2, (I), with MCl–HCl in acetone leads to chloride-bridge cleavage with formation of M[RuCl3(CS)(PPh3)2](M = Ph4As+, Ph3(PhCH2)P+, or Et4N+), (II). Areinvestigation of the reaction between the complex [RuCl2(PPh3)3] and CS2 reveals that, in addition to the previously reported [RuCl(η-CS2)(PPh3)3]Cl and (I), another thiocarbonyl complex, (III), with very similar physicochemical properties to (I) is also formed. Full analytical data and 31P n.m.r. studies, together with an X-ray crystallographic study, show that complex (III) is the tri-µ-chloro-species [(PPh3)2ClRuCl3Ru(CS)(PPh3)2]. Although no evidence has been found for conversion of complex (I) into (III), prolonged shaking of an acetone solution of (I) gives a small amount of [(PPh3)(CS)ClRuCl3Ru(CS)(PPh3)2],Me2CO, (IV). Reaction of complex (III) with concentrated hydrochloric acid gives paramagnetic [(PPh3)Cl2RuCl3Ru(CS)(PPh3)2],2Me2CO, (V), which contains ruthenium in formal oxidation states of (III) and (II).

(Bicyclo[2.2.1]hepta-2,5-diene)carbonyltrihalogenoruthenate(II) complexes

The preparation of the first anionic ruthenium(II) diene complexes M[RuX3CO(C7H8)]{M = Ph3(PhCH2)P+ or Cs+; X = Cl or Br; C7H8= bicyclo[2.2.1]hepta-2,5-diene (norbornadiene)}via cleavage of [RuCl2CO(C7H8)]n with halide ion are reported. Detailed 1H n.m.r. and homonuclear decoupling studies indicate a structure with the carbonyl and a halide group co-ordinated cis to the diene. Reaction of the complex [RuCl2CO(C7H8)]n with Ph4AsCl,HCl in acetone gives a mixture of inseparable products, but when heated under reflux only cis-(Ph4As)2[RuCl4(CO)2] is isolated.

The protein-polysaccharide complex of bovine nasal cartilage Studies on the molecular organisation

1. 1. The light fraction of the protein-polysaccharide complex of bovine nasal cartilage is split by treatment with 0.1 M HCl in acetone into two fragments characterised by a sedimentation coefficient of 2.3 and 8.1 S, respectively. The chemical composition of the mixture is basically identical to that of the untreated protein-polysaccharide complex, but amino acid analysis of the protein component reveals a reduction in the concentration of a few amino acids, notably tyrosine. Amino endgroup analysis shows four N-terminal amino acids: aspartic acid, valine, leucine and isoleucine in molar ratio 1:1:0.7:0.3. A number average molecular weight of approx. 41 000 is derived. 2. 2. Cleavage of the acetone-treated proteoglycan with N-bromosuccinimide reduces the protein content by 30%. The 8.1-S fragment is no longer detectable and the whole material behaves in ultracentrifugal analysis as a single 2.2-S peak. A number average molecular weight of approx. 33 000 is determined by N-terminal analysis. 3. 3. Xylose estimation is in agreement with the presence of two polysaccharide chains per 33 000 mol. wt. fragment. 4. 4. A model is proposed in which the molecular unit of the protein-polysaccharide complex is composed of three 33 000 mol. wt. sub-units each of which consists of a polypeptide core and two polysaccharide chains. Many of these molecular units are linked together in an end-to-end arrangement.

Opposide, proposed structure

AbstractThe hypothetical structure 1 is proposed for opposide (C29H44O11), a new glycoside from the seeds of Acokanthera oppositifolia (LAM.) CODD. Opposide is derived from the new aglycone gratogenin, which is most probably the 1β, 3β, 5β, 11α, 14β‐pentahydroxy‐card‐20:22‐enolide (8) (C23H34O7) and which is bound glycosidically through position 3 to the α‐pyranosidic form of 6‐desoxy‐L‐talose. The hydrolysis of opposide by HCl in acetone gave an anhydrogenin (C23H32O6) instead of the intact aglycone. In analogy to the reaction sequence observed by VOLPP and TAMM for ouabagenin, the structure of the anhydrogenin is deduced to be that of a 3β, 5β, 14β‐trihydroxy‐1α, 11α‐epoxy‐card‐20:22‐enolide (6). The above mentioned structures are based on the course of acetylation and especially on NMR.‐spectra.

Paper chromatography of inorganic ions : XVII. the paper chromatography of Pa(V)

The paper chromatography of Pa(V) in acetoneHClwater mixtures has been studied. The movemet of Pa(V) as well as of ther cations may be expressed by the equation pK  RM + 2x pCl- + K providing the ratio acetone to HCl + water is constant (90:10).