Heating with water

It is prepared by fully chlorinating toluene. When heated with water at 100°C, or with lime, benzoic acid is obtained, benzoyl The group PhC(O)-. 

Colourless prisms m.p. 130 C. Manufactured by treating maleic anhydride with water. It is converted to the anhydride by heating at By prolonged heating at 150 "C or by heating with water under pressure at 200 C, it is converted to the isomeric (trans) fumaric acid. Reduced by hydrogen to succinic acid. Oxidized by alkaline solutions of potassium permanganate to mesotartaric acid. When heated with solutions of sodium hydroxide at 100 C, sodium( )-malate is formed. Used in the preparation of ( )-malic acid and in some polymer formulations. 

C (rapid heating). Manufactured by the oxidation of lactose or the galactans from wood with nitric acid. When heated with water it forms a soluble lactone. Converted to furoic... 

To distinguish these anhydrides from the corresponding acids, note that succinic anhydride (m.p. 120°) is almost insoluble in cold water, whereas succinic acid (m.p. 185 ) is readily soluble. Phthalic anhydride has m.p. 132° and phthalic acid has m.p. 196-199° with decomposition. Each of these anhydrides when heated with water hydrolyses to the corresponding acids. 

Acetonylacetone is available commercially as a by-product of the manufacture of acetic acid from acetylene. It may be prepared by condensation of chloroacetone with ethyl sodioacetoacetate the resulting ethyl acetonylacetoacetate when heated with water under pressure at 160° undergoes ketonic scission to give acetonylacetone. 

Ester hydrolysis is the most studied and best understood of all nucleophilic acyl sub stitutions Esters are fairly stable in neutral aqueous media but are cleaved when heated with water m the presence of strong acids or bases The hydrolysis of esters m dilute aqueous acid is the reverse of the Eischer esterification (Sections 15 8 and 19 14)... 

Methylene chloride is one of the more stable of the chlorinated hydrocarbon solvents. Its initial thermal degradation temperature is 120°C in dry air (1). This temperature decreases as the moisture content increases. The reaction produces mainly HCl with trace amounts of phosgene. Decomposition under these conditions can be inhibited by the addition of small quantities (0.0001—1.0%) of phenoHc compounds, eg, phenol, hydroquinone, -cresol, resorcinol, thymol, and 1-naphthol (2). Stabilization may also be effected by the addition of small amounts of amines (3) or a mixture of nitromethane and 1,4-dioxane. The latter diminishes attack on aluminum and inhibits kon-catalyzed reactions of methylene chloride (4). The addition of small amounts of epoxides can also inhibit aluminum reactions catalyzed by iron (5). On prolonged contact with water, methylene chloride hydrolyzes very slowly, forming HCl as the primary product. On prolonged heating with water in a sealed vessel at 140—170°C, methylene chloride yields formaldehyde and hydrochloric acid as shown by the following equation (6). 

Chloroform and water at 0°C form six-sided crystals of a hydrate, CHCl I8H2O [67922-19-41which decompose at 1.6°C. Chloroform does not decompose appreciably when in prolonged contact with water at ordinary temperature and in the absence of air. However, on prolonged heating with water at 225°C, decomposition to formic acid, carbon monoxide, and hydrogen chloride occurs. A similar hydrolysis takes place when chloroform is decomposed at elevated temperature by potassium hydroxide. 

Hydrolysis. 1,1,1-Trichloroethane heated with water at 75—160°C under pressure and in the presence of sulfuric acid or a metal chloride catalyst decomposes to acetyl chloride, acetic acid, or acetic anhydride (54). However, hydrolysis under normal use conditions proceeds slowly. The hydrolysis is 100—1000 times faster with trichloroethane dissolved in the water phase than vice versa. Refluxing 1,1,1-trichloroethane with ferric and gallium chloride... 

When the alkaloid is heated with water at 150°, or boiled with dilute acids, it is hydrolysed into hydrocotarnine, and opianic acid. Similar decompositions are induced by acid oxidation or acid reduction, thus (1) dilute nitric acid furnishes opianic acid, CjoHioOj, and cotarnine, C12H15O4N (2) zinc and hydrochloric acid produce meconin, C10H10O4, and hydrocotarnine, C12H15O3N. 

When bisdiazoacetic estei is heated with water 01 dilute aud It breaks up into hydiazine and o.xahc acid. 

The N-carboxybenzoyl compound (2.7 g) was refluxed for 30 minutes with acetic anhydride (10 ml), the mixture taken to dryness (vacuum) and the residue heated with water. The cooled gummy product became granular on rubbing and crystallized from methyl ethyl ketone-petrol or aqueous ethanol in almost colorless needles, MP 184° to 186°C, of p-nitro-N-phthaloyl-D L-phenylalanine. 

A mixture of 50 parts of the distillate, 25.6 parts of 3-bromoethyl acetate, 10.7 parts of potassium carbonate and 400 parts of toluene is stirred at reflux temperature for 16 hours. The mixture is heated with water. The organic layer is separated, washed with water and extracted with dilute hydrochloric acid. The resulting extract is washed with benzene, rendered alkaline and extracted with benzene. The resulting benzene solution is dried over anhydrous potassium carbonate, filtered and concentrated. The residue is dissolved in 300 parts of ethanol and treated with 2.2 equivalents of a 25% solution of anhydrous hydrochloric acid in 2-pro-pa nol. The resulting crystals are recrystallized from 400 parts of ethanol and 10 parts of water. The dihydrochloride of N-( 3-acetoxyethyl)-N -[7-(2 -chloro-10 -phenothiazine)propyl] piperazine melts unsharply at about 200°C to 230°C. 

Curtius rearrangement (Section 24.6) The conversion of an acid chloride into an amine by reaction with azide ion, followed by heating with water. 

Now we might think of the mechanical engineer who is designing a boiler to be heated with water gas fuel. He is interested in burning the... 

An example of a reversible reaction in the liquid phase is afforded by the esterification reaction between ethanol and acetic (ethanoic) acid forming ethyl acetate and water. Since, however, ethyl acetate undergoes conversion to acetic acid and ethanol when heated with water, the esterification reaction never proceeds to completion. 

Methoxy-3//-l,4-benzodiazepine (2) gives methyl 2-aminobenzoate when heated with water.213... 

Applications of PCM cover many diverse fields. As mentioned before, the most important selection criterion is the phase change temperature. Only an appropriate selection ensures repeated melting and solidification. Connected to the melting and solidification process is the heat flux. The range of heat flux in different applications covers a wide range from several kW for space heating with water or air, domestic hot water and power plants to the order of several W for temperature protection and transport boxes (Figure 124). 

Allyl phenyl ether was heated with water in the MBR for 1 h at different temperatures [46]. It underwent Claisen rearrangement to 2-allylphenol (56% yield) at 200 °C, 2-(2-hydroxyprop-l-yl)phenol (37% yield) at 230 °C and 2-methyl-2,3-dihydro-furan (72% yield) at 250 °C (Scheme 2.12). Support for the reaction sequence was obtained through experiments with authentic intermediates. 

It was also found that the degree of hydration of the complex affected the rate of racemization. Generally, the hydrated complexes reacted faster than anhydrous samples. It was also found that reducing the particle size increased the rate of racemization, but when the iodide compound was heated with water in a sealed tube, the racemization was slower than for the hydrated solid from which the water could escape. The fact that the hydrated samples racemized faster could indicate that an aquation-anation mechanism is involved, but the results obtained in the sealed tube experiments do not agree with that idea. 

Guillini A process for making gypsum from the waste product from the Wet Process for making phosphoric acid. The waste is heated with water in an autoclave this removes impurities and converts the calcium sulfate dihydrate to the hemi-hydrate. 

Smaller amounts of substance can also be steam distilled from a distilling flask of sufficient size having the side tube attached high up on the neck, and specially volatile substances can also be distilled by simple heating with water, without a current of steam. 

Since the ozonides are decomposed on heating with water, in accordance with the equation... 

There is evidence that gyrometrin does not exist in the free state in the mushroom, but rather is bound to an unknown high-molecular component. Therefore, fruiting bodies have to be heated with water in a closed tube at 120°C for several hours before methylhydrazine can be extracted with chloroform under an atmosphere of nitrogen. Gas chromotography and TLC have been used for its identification. 

When heated with water, the compound decomposes to metallic gold and gold trichloride ... 

After separating the oxide it was converted to ethyleneglycol by heating with water and then nitrated with mixed acid 5) Preparation of NGc by duPonl Method, in which formaldehyde is reacted with carbon monoxide and water to form glycolic acid ... 

JZRnrtton.—Ethylio iodide, vbea heated with water in a sealed tube, produces ether md hydriodio acid... 

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