Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Acetone hydrate formed from

The formation of niclosamide hydrates, and the effect of relative humidity on the solvatomorphs obtained from acetone and ethyl acetate has been studied [79], The acetone and ethyl acetate solvatomorphs could be desolvated, and exposure to elevated humidity resulted in the formation of two hydrate structures. Each hydrate could be dehydrated into a different anhydrate phase, but only the hydrate formed from the acetone desolvate could be rehydrated to form a hydrate phase. Dynamic vapor sorption has been used to develop a method for determining the onset relative humidity of a glass transition and associated crystallization process [80]. [Pg.273]

This can be illustrated by comparing the amount of hydrate formed from formaldehyde, acetaldehyde, and acetone. [Pg.802]

Furalazine, Acetylfuratrizine, Panfuran-S. Heating nitrovin in butanol or dimethylformamide at 100—130°C affords furalazine, 6-[2-(5-nitro-2-furanyl)ethenyl]-l,2,4-triazine-3-amine (34). An improved synthesis originates with 5-nitro-2-furancarboxaldehyde and acetone, proceeds through 4-(5-nitro-2-furanyl)-3-buten-2-one followed by a selenium dioxide oxidation to the pymvaldehyde hydrate, and subsequent reaction with aininoguariidine (35). Furalazine, acetylfuratrizine (36), and the A[-A/-bis(hydroxymethyl) derivative, Panfuran-S, formed from the parent compound and formaldehyde (37), are systemic antibacterial agents. [Pg.461]

We wish to report several metal complexes formed from a phosphorous acid diester of the type OP (H) (OR) 2 which underwent isomerization to form a metal-phosphorus bond as in (a). In the course of our investigations on the complexing properties of polycylic phosphites (9 17) j it was found that 2,8,9-trioxa-l-phosphaadamantane (L) undergoes a rapid, acid hydrolysis in acetone to form two colorless, crystalline hydrolysates, A and B. Only isomer A or L complexed with divalent hydrated metal ions, and it is concluded from infrared evidence that A has isomerized as shown in the following reaction sequence. Supporting infrared and PNMR evidence is presented for the tentatively postulated structures of A and B. [Pg.606]

The specific properties of hydrated hydrotalcites appear not only in the aldoli-zation of acetone, but in many other aldolization reactions. For example, in the aldol condensation of benzaldehyde with acetone the hydrated form catalyzes the reaction at 273 K, yielding aldol as the main product instead of benzalacetone, obtained on the calcined sample. Competitive adsorption kinetics are still observed, with a much greater adsorption coefficient for benzaldehyde. As suggested earlier from Hammett relationships, this reaction can be generalized with success to many substituted benzaldehydes [32], although the reaction could be performed selectively at 273 K with benzaldehyde only, and substituted benzaldehydes required a reaction temperature of 333 K. Because of this high temperature the reaction usually gives a, unsaturated ketones isolated yields are > 95 %. [Pg.334]

Hydrated crystals from water, mp 135-140, resolidifies with second mp 190-193. Melting point taken after drying at 56 and 8 mm. —78 (c — 1.99 in ethanol), uv max (pH 6.3) 280 nm (e 50). pKa, 8.8. Basic reaction. Readily forms salts with acids. Soly in water —2 mg/ml. Freely sol in alcohols, acetone, chloroform, acetonitrile, ethyl acetate. Moderately sol in ether, ethylene dtchloride, amyl acetate. [Pg.578]

Compound 63 is most probably formed from cis or trans isohumulone (65, 66, Fig. 31), following epoxidation of the side chain at C-5. Opening of the epoxide may be accompanied by loss of acetone. The bicyclic intermediate can cyclize again after hydration of the remaining double bond. [Pg.76]

Ruthenium (IV) oxide [12036-10-1] M 133.1, d 6.97. Freed from nitrates by boiling in distilled water and filtering. A more complete purification is based on fusion in a KOH-KNO3 mix to form the soluble ruthenate and perruthenate salts. The melt is dissolved in water, and filtered, then acetone is added to reduce the ruthenates to the insoluble hydrate oxide which, after making a slurry with paper pulp, is filtered and ignited in air to form the anhydrous oxide [Campbell, Ortner and Anderson Anal Chem 33 58 1961]. [Pg.461]

Bromo-l-phthalimidopentane 3 was obtained in 72-82 g yield by refluxing 92 g of 1,4-dibromopentane 1, 55.5 g of potassium phthalimide 2, and 200 mL dry acetone on a steam bath for 30 h. Compound 3 (30 g) and 42 g 6-methoxy-8-aminoquinoline 4 refluxed at 130-135 °C for 6 h, extracted with benzene to separate insoluble 6-methoxy-8-aminoquinoline hydrobromide, the residue from evaporation of the benzene was refluxed with stirring with 100 mL of an alcoholic solution of 6 g hydrazine hydrate for 4 h, the solution was concentrated, made acidic to Congo red with 8 N hydrochloric acid, filtered, and washed with boiling water. The combined filtrate and washings was concentrated, made alkaline, extracted with benzene, and distilled in vacuo to give 20.5 g primaquine 6, which was treated with 19 mL 85% phosphoric acid in absolute ethanol, formed 42.5% primaquine diphosphate. [Pg.157]

The lustrous black crystals of trirhenium nonabromide are not rapidly degraded on exposure to the atmosphere the crystals can be stored over desiccants for months without evidence of decomposition. The bromide dissolves fairly slowly and sparingly in ether and acetone. In methanol, the bromide gives yellow-orange solutions, but it is solvolyzed within minutes. Similarly, the bromide dissolves in water at room temperature to yield a violet solution which darkens rapidly, yielding a black precipitate, presumably the hydrated dioxide.9 Contrary to published work,10 the bromide does dissolve in ammonia with solvolysis, as is evidenced by lines attributable to ammonium bromide in x-ray diffraction data of the solid residue recovered from liquid ammonia solutions.11 Trirhenium nonabromide reacts with Lewis bases such as phosphines and amines to form a series of complexes of the type (base) 3Re3Br9.6... [Pg.61]

Water has also been shown to be essential for the liquid phase polymerization of isobutylene with stannic chloride as catalyst (Norrish and Russell, 87). The rates of reaction were measured by a dilatometric method using ethyl chloride as common solvent at —78.5°. With a mixture consisting of 1.15% stannic chloride, 20 % isobutylene, and 78.8% ethyl chloride, the rate of polymerization was directly proportional to the amount of added water (up to 0.43% of which was added). A rapid increase in the rate of polymerization occurred as the stannic chloride concentration was increased from 0.1 to 1.25% with higher concentrations the rate increased only gradually. It was concluded that a soluble hydrate is formed and functions as the active catalyst. The minimum concentration of stannic chloride below which no polymerization occurred was somewhat less than half the percentage of added water. When the concentration of the metal chloride was less than about one-fifth that of the added water, a light solid precipitated formation of this insoluble hydrate which had no catalytic activity probably explains the minimum catalyst concentration. The addition of 0.3% each of ethyl alcohol, butyl alcohol, diethyl ether, or acetone in the presence of 0.18% water reduced the rate to less than one-fifth of its normal value. On the other hand, no polymerization occurred on the addition of 0.3 % of these substances in the absence of added water. The water-promoted reaction was halved when 1- and 2-butene were present in concentrations of 2 and 6%, respectively. [Pg.75]

Hydrated compounds of the type U02(H2L) xH20 have been reported for 1,2-diamino-propane-Af.NjA jAf -tetraacetic acid (x unspecified), tram diaminocyclohexane-N,N,N, N -tetraacetic acid (x = 0 or 3 (U02)2L-xH20, with x = 0 or 6 also known), 2,2 -diaminodiethyl ether-A, A,N, N -tetraacetic acid (x = 3), and 2,2 -diaminodiethyl sulfide-N,N,N, N -tetra-acetic acid (x = 0 or 4) the hydrates are predpitated from aqueous media, but in the last instance a mixture of ethanol and acetone was added to induce precipitation. The analogous di(2-aminoethoxy)ethane-/V, N,N, N -tetraacetic acid (H4L) forms the compounds... [Pg.1213]

The lanthanide salt hydrates and D were taken in the ratio Ln D 1 (2 3). Their mixture and 12 ceramic balls (d= 8-10 mm) were put into a corundum thick-wall reactor (volume 150mL) and exposed to the vibration (50 Hz, 1.5 kW) for 3-15 min. Then small amounts of solvents (ethanol, water, hexane, 3-10 mL) were added. The formed solid was recrystallized from acetone. Yields 85-92%. [Pg.279]


See other pages where Acetone hydrate formed from is mentioned: [Pg.227]    [Pg.133]    [Pg.465]    [Pg.224]    [Pg.92]    [Pg.266]    [Pg.611]    [Pg.66]    [Pg.183]    [Pg.124]    [Pg.461]    [Pg.1972]    [Pg.253]    [Pg.458]    [Pg.30]    [Pg.284]    [Pg.103]    [Pg.464]    [Pg.381]    [Pg.79]    [Pg.234]    [Pg.87]    [Pg.209]    [Pg.183]    [Pg.29]    [Pg.769]    [Pg.326]    [Pg.30]    [Pg.195]    [Pg.103]    [Pg.1656]    [Pg.216]    [Pg.196]    [Pg.530]   
See also in sourсe #XX -- [ Pg.802 ]




SEARCH



Acetone from

Acetone hydrate

Acetone hydration

© 2024 chempedia.info