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With chloroform

It forms excellent freezing mixtures with many organic liquids, e.g., with alcohol, — 72° with ether, — 77° and with chloroform, — 77°. [Pg.39]

Tl>e base is only slightly soluble in ether, thus rendering its use uneconomical. It may be extracted with chloroform and precipitated from the dried chloroform solution with carbon tetrachloride. [Pg.574]

From phenols by interaction with chloroform and sodium hydroxide solution (Reimer - Tiemann reaction), for example ... [Pg.691]

The methyl benzoate is removed by extraction with chloroform, and upon cautious acidification of the aqueous layer perbenzoic acid is liberated the latter is extracted with chloroform and is usually preserved as a solution in this solvent ... [Pg.807]

Treatment of 3 5 dimethylphenol with dilute nitnc acid followed by steam distillation of the reaction mixture gave a compound A (CgH9N03 mp 66°C) in 36% yield The nonvolatile residue from the steam distillation gave a compound B (CsHpNOs mp 108°C) in 25% yield on extraction with chloroform Identify compounds A and B... [Pg.1022]

Compatibihty of acetone with other materials should be carefliUy considered, especially in disposal of wastes. It reacts with chlorinating substances to form toxic chloroketones, and potentially explosively with some peroxy compounds and a number of oxidizing mixtures. Mixed with chloroform, acetone will react violently in the presence of bases. Other incompatibilities ate Hsted in the Sax handbook (53). [Pg.98]

Resorcinol carboxylation with carbon dioxide leads to a mixture of 2,4-dihydroxyben2oic acid [89-86-1] (26) and 2,6-dihydroxyben2oic acid [303-07-1] (27) (116). The condensation of resorcinol with chloroform under basic conditions, in the presence of cyclodextrins, leads exclusively to 2,4-dihydroxyben2aldehyde [95-01-2] (28) (117). Finally, the synthesis of l,3-bis(2-hydroxyethoxy)ben2ene [102-40-9] (29) has been described with ethylene glycol carbonate in basic medium (118), in the presence of phosphines (119). Ethylene oxide, instead of ethyl glycol carbonate, can also be used (120). [Pg.492]

Although 4-hydroxybenzaldehyde can be made by the saligenin route, it has been made historically by the Reimer-Tiemann process, which also produces sahcylaldehyde (64). Treatment of phenol with chloroform and aqueous sodium hydroxide results in the formation of benzal chlorides, which are rapidly hydrolyzed by the alkaline medium into aldehydes. Acidification of the phenoxides results in the formation of the final products, sahcylaldehyde and 4-hydroxybenzaldehyde. The ratio of ortho and para isomers is flexible and can be controlled within certain limits. The overall reaction scheme is shown in Figure 1. Product separation is accomphshed by distillation, but this process leads to environmental problems because of the quantities of sodium chloride produced. [Pg.506]

Solvent extraction techniques are useful in the quantitative analysis of niobium. The fluoro complexes are amenable to extraction by a wide variety of ketones. Some of the water-insoluble complexes with organic precipitants are extractable by organic solvents and colorimetry is performed on the extract. An example is the extraction of the niobium—oxine complex with chloroform (41). The extraction of the niobium—pyrocatechol violet complex with tridodecylethylammonium bromide and the extraction of niobium—pyrocatechol—sparteine complex with chloroform are examples of extractions of water-soluble complexes. Colorimetry is performed on the extract (42,43). Colorimetry may also be performed directly on the water-soluble complex, eg, using ascorbic acid and 5-nitrosahcyhc acid (44,45). [Pg.25]

Ahyl alcohol undergoes reactions typical of saturated, aUphatic alcohols. Ahyl compounds derived from ahyl alcohol and used industriahy, are widely manufactured by these reactions. For example, reactions of ahyl alcohol with acid anhydrides, esters, and acid chlorides yield ahyl esters, such as diahyl phthalates and ahyl methacrylate reaction with chloroformate yields carbonates, such as diethylene glycol bis(ahyl carbonate) addition of ahyl alcohol to epoxy groups yields products used to produce ahyl glycidyl ether (33,34). [Pg.74]

Pyrroles may be ring-expanded to pyridines in reactions having a greater academic than practical interest. Treatment of pyrrole with chloroform and sodium ethoxide (in effect, with dichlorocarbene, CCl2) gives a low yield of 3-chloropyridine [626-60-8]. A much better yield (33%) is obtained if chloroform and pyrrole are heated together in the vapor phase at 550°C some 2-chloropyridine (17) is also formed (71). [Pg.332]

Miscellaneous Reactions. The Reimer-Tiemaim reaction of sahcyhc acid (1) with chloroform and alkah (eq. 1) results in the 3- and 5-formyl derivatives. If the reaction is carried out with carbon tetrachloride, the corresponding dicarboxyhc acids form (eq. 2). The products (2) and (3) are 2-hydroxy-l,3-ben2enedicarboxyhc acid [606-19-2] and 4-hydroxy-l,3-ben2enedicarboxyhc acid [636-46-4] respectively. [Pg.285]

Aroclor 1248, Aroclor 1254, and Aroclor 1260. Quantitation is by comparison of chromatograms with standard concentrations of pure compounds treated in an identical manner. The phenoxy acid herbicides (2,4-dichlorophenoxy)acetic acid (2,4-D), sUvex, and (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T) can be deterrnined by electron-capture detection after extraction and conversion to the methyl esters with BF.-methanol. The water sample must be acidified to pH <2 prior to extraction with chloroform. [Pg.233]

Hydroxyhc Compounds. Chloioformates on reaction with water give the patent hydroxy compound, HCl, and CO2 as weU as the symmetrical carbonate formed by the reaction of the hydroxy compound with chloroformate. [Pg.38]

Aliphatic Alcohols and Thiols. Ahphatic alcohols on reaction with chloroformates give carbonates and hydrogen chloride. Frequendy, the reaction proceeds at room temperature without a catalyst or hydrogen chloride acceptor. However, faster reactions and better yields are obtained in the presence of alkaU metals or their hydroxides, or tertiary amines. Reactions of chloroformates with thiols yield monothiolocarbonates (14). [Pg.38]

Heterocyclic Alcohols. Thek reactions with chloroformates lead to carbonates. Thus furan- and tetrahydrofuran-derived alcohols give the corresponding carbonates in 75% yield (15). Inorganic bases and tertiary amines as acid acceptors increase the rate and yield in this reaction. [Pg.39]

Methanol, heated at 250°C with chloroform or carbon tetrachloride in contact with active carbon, is converted in part to methyl chloride (52). Methyl chloride has been produced from methoxymagnesium chloride, CH OMgCl, a by-product from the manufacture of certain organo—sHicon compounds, by heating over 200°C (53). [Pg.514]

The ACGIH recommended maximum time-weighted average concentration in the workplace atmosphere for eight-hour daily exposure is 10 ppm. OSHA has set the permissible exposure level at 2 ppm. It maybe desirable to exclude alcohoHcs, persons with chronic disorders of the Hver, kidneys, and central nervous system, and those with nutritional deficiencies from working with chloroform. [Pg.527]

In Example 1 the solute, acetone, contains a ketone carbonyl group which is a hydrogen acceptor, i.e., solute class 5 according to Table 15-4. This solute is to be extracted from water with chloroform solvent which contains a hydrogen donor group, i.e., solvent class 4. The solute class 5 and solvent class 4 interaction in Table 15-4 is shown to give a negative deviation from Raonlt s law. [Pg.1452]

Hydroxyquinoline forms the complex with Cu(II) in ratio 1 1 at pH 5-7. The composition of the complex is changed on 1 2 at pH>7. 8-Hydroxy-quinoline accepts bromine therefore its excess has been removed with NaOH solution. The complex was extracted with chloroform. It was shown that double extraction was enough to extract the complex. The detection limit is 5x10 M during 10c and at current generation IxlO A. [Pg.149]

Cellulose for chromatography is purified by sequential washing with chloroform, ethanol, water, ethanol, chloroform and acetone. More extensive purification uses aqueous ammonia, water, hydrochloric acid, water, acetone and diethyl ether, followed by drying in a vacuum. Trace metals can be removed from filter paper by washing for several hours with O.IM oxalic or citric acid, followed by repeated washing with distilled water. [Pg.21]

Acetic acid with chloroform, ethanol, ethyl acetate, acetonitrile, petroleum ether, or water. [Pg.37]

Methanol with chloroform, diethyl ether, glycerol or water. [Pg.37]

Solid CO2 with chloroform or acetone Solid CO2 (powdered CO2 snow)... [Pg.38]

Ethers that are solids (e.g. phenyl ethers) can be steam distilled from an alkaline solution which will hold back any phenolic impurity. After the distillate is made alkaline with sodium carbonate, the insoluble ether is collected either by extraction (e.g. with chloroform, diethyl ether or toluene) or by filtration. It is then crystallised from alcohols, alcohol/petroleum ether, petroleum ether, toluene or mixtures of these solvents, sublimed in a vacuum and recrystallised if necessary. [Pg.65]

It diagramatically represents a silica surface in contact with a low concentration of chloroform in n-heptane where the surface is partly covered with chloroform, the remainder covered with n-heptane. The solute molecules can either rest on the surface of the chloroform layer or on the surface of the layer of adsorbed n-heptane. [Pg.99]


See other pages where With chloroform is mentioned: [Pg.19]    [Pg.28]    [Pg.83]    [Pg.228]    [Pg.269]    [Pg.62]    [Pg.415]    [Pg.479]    [Pg.541]    [Pg.978]    [Pg.1040]    [Pg.30]    [Pg.45]    [Pg.747]    [Pg.301]    [Pg.233]    [Pg.246]    [Pg.260]    [Pg.25]    [Pg.51]    [Pg.55]    [Pg.28]    [Pg.176]   
See also in sourсe #XX -- [ Pg.567 ]




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2- ethylamine reaction with ethyl chloroformate

9-Fluorenylmethyl chloroformate reaction with amino acids

Alkyl chloroformates, alkylation with

Alkylation of Aromatics with Alkyl Chloroformates and Oxalates

Amines cleavage with phenyl chloroformate

Amines reaction with chloroform

Amines reaction with chloroformates

Amines with chloroformates

Benzimidazoles reaction with chloroform

Benzoin, reaction with chloroform

Chloroform extraction with

Chloroform reaction with phenoxide

Chloroform, condensation with benzaldehyde

Chloroform, direct reaction with

Chloroform, palladium complexes with

Chloroform, reaction with 1-octene

Chloroform, reaction with base

Chloroform, reaction with bromine

Chloroform, solution preparation, with

Chloroform, solution preparation, with phenol

Chloroformate, benzyl, reaction with amines

Chloroformates with tert amines

Chloroformates, addition benzyl, with amines

Chloroformates, addition with Grignard reagents

Chloroformates, reaction with

Chloroformates, reaction with polysaccharides

Chloroformic esterification with

Clusterization of Water in Ternary Systems with DMSO or Acetonitrile and Chloroform

Condensation, of triphenylphosphine with chloroform

Diphenylamine, reaction with chloroform

Drugs deriv with chloroformates

Ethyl chloroformate, reaction with enamines

Ethylamine, reaction with chloroform

Extraction with chloroform/methanol

Fluoroethanol reaction with ethyl chloroformate

Glycosphingolipids with chloroform/methanol, extraction

Imidazoles reaction with chloroform

Phenol with chloroform

Reaction with chloroform

Reaction with ethyl chloroformate

Tertiary amines with chloroformates

The Corrosion Debacle in Extracting Furfural with Chloroform

Toluene, complex with chloroform

With benzyl chloroformate

With chloroformates

With chloroformates

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