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Hydrolyzates

The major portion of sait is found in residues as these streams serve as the bases for fuels, or as feeds for asphalt and petroleum coke production, the presence of salt in these products causes fouling of burners, the alteration of asphalt emulsions, and the deterioration of coke quality. Furthermore, calcium and magnesium chlorides begin to hydrolyze at 120°C. This hydrolysis occurs rapidly as the temperature increases (Figure 8.1) according to the reaction i. ... [Pg.329]

Derive the equation of state, that is, the relationship between t and a, of the adsorbed film for the case of a surface active electrolyte. Assume that the activity coefficient for the electrolyte is unity, that the solution is dilute enough so that surface tension is a linear function of the concentration of the electrolyte, and that the electrolyte itself (and not some hydrolyzed form) is the surface-adsorbed species. Do this for the case of a strong 1 1 electrolyte and a strong 1 3 electrolyte. [Pg.95]

Stable to acid removed with base more difficult to hydrolyze than esters... [Pg.66]

Silcones are important products of silicon. They may be prepared by hydrolyzing a silicon organic chloride, such as dimethyl silicon chloride. Hydrolysis and condensation of various substituted chlorosilanes can be used to produce a very great number of polymeric products, or silicones, ranging from liquids to hard, glasslike solids with many useful properties. [Pg.34]

METHOD 1 Strike s sentimental favorite. The one Strike has dreamt about so very often. This method involves taking hydrogen peroxide and formic acid to form a temporary intermediate which is subsequently hydrolyzed with sulfuric acid to give the ever-lovely ketone. [Pg.53]

Since the formamide reaction solution is going to be a lot cleaner than the tarry mess of the original recipe, the chemist has yet another option to explore. Instead of hydrolyzing in the reaction pot, the chemist can add SOOmL of clean dHjO and stir just like in the crappy original method except that this time the chemist is going to look for a heavy oil layer that will settle at the bottom. The up-... [Pg.113]

After 5 hours the reaction is stopped and the flask cooled. The formyl-MDA can be isolated and hydrolyzed by any of the ways Strike just mentioned a few paragraphs back, but this method offers a third, very convenient way which should be tried. What the chemist does is forget about letting the flask and its contents cool. Instead, she removes the oil bath, places the flask back on the stirplate (distillation setup still attached), attaches a vacuum and distills off all the formamide. What remains is a dark, heavy formyl-MDA precipitate that is allowed to cool down while the chemist makes up a solution of 150g potassium hydroxide (KOH), 500mL ethanol and 125mL dH20. This solution is poured into the... [Pg.114]

METHOD 5 Contributed by Osmium [53], The paper reads (at least to Strike) that this reduction method can work to reduce the formyl intermediate made in the Leuckart reaction directly into MDMA instead of needing to hydrolyze to MDA with HCi (don t ask). For this reaction one substitutes an equimolar amount of p-Nitropropene for the 3,4-dimethoxybenzylcyanide in the representative experimental below ... [Pg.141]

Exp. 4) in 10 min with cooling at -30°C. After an additional 15 min 0.30 mol of a-chlororaethyl ethyl ether (note 2) was introduced in 10 min, while keeping the temperature between -20 and -30°C. A white precipitate of lithium chloride was formed. The cooling bath was then removed and the temperature was allowed to rise to +10°C. The mixture was hydrolyzed by shaking it with 200 ml of a solution of 30 g of ammonium chloride, to which 5 ml of aqueous ammonia had been added. [Pg.40]

Alkylation of the dilithiated sulfide can be performed by adding at -10°C 0.12 mol of an alkyl bromide, allowing the temperature to rise to 20-30°C and hydrolyzing the reaction mixture after stirring for an additional 45 min at about 25°C. [Pg.55]

A mixture of 0.10 mol of freshly distilled 3-methyl-3-chloro-l-butyne (see Chapter VIII-3, Exp. 5) and 170 ml of dry diethyl ether was cooled to -100°C and 0.10 mol of butyllithium in about 70 ml of hexane was added at this temperature in 10 min. Five minutes later 0.10 mol of dimethyl disulfide was introduced within 1 min with cooling betv/een -100 and -90°C. The cooling bath vjas subsequently removed and the temperature was allowed to rise. Above -25°C the clear light--brown solution became turbid and later a white precipitate was formed. When the temperature had reached lO C, the reaction mixture was hydrolyzed by addition of 200 ml of water. The organic layer and one ethereal extract were dried over potassium carbonate and subsequently concentrated in a water-pump vacuum (bath... [Pg.75]

A solution of 0.21 mol of butyllithium in about 140 ml of hexane (note 1) was cooled below -40°C and 90 ml of dry THF ivere run in. Subsequently a cold (< -20 C) solution of 0.25 nol of propyne in 20 ml of dry THF was added with cooling below -20°C and a white precipitate was formed. A solution of 0.10 mol of anhydrous (note 2) lithium bromide in 30 ml of THF was added, followed by 0.20 mol of freshly distilled cyclopentanone or cyclohexanone, all at -30°C. The precipitate had disappeared almost completely after 20 min. The cooling bath was then removed and when the temperature had reached 0°C, the mixture was hydrolyzed by addition of 100 ml of a solution of 20 g of NHi,Cl in water. After shaking and separation of the layers four extractions with diethyl ether were carried out. The extracts were dried over magnesium sulfate and the solvents removed by evaporation in a water--pump vacuum. Careful distillation of the remaining liquids afforded the following... [Pg.75]

The following acid-catalyzed cyclizations leading to steroid hormone precursors exemplify some important facts an acetylenic bond is less nucleophilic than an olelinic bond acetylenic bonds tend to form cyclopentane rather than cyclohexane derivatives, if there is a choice in proton-catalyzed olefin cyclizations the thermodynamically most stable Irons connection of cyclohexane rings is obtained selectively electroneutral nucleophilic agents such as ethylene carbonate can be used to terminate the cationic cyclization process forming stable enol derivatives which can be hydrolyzed to carbonyl compounds without this nucleophile and with trifluoroacetic acid the corresponding enol ester may be obtained (M.B. Gravestock, 1978, A,B P.E. Peterson, 1969). [Pg.279]

Trifluoroacetimidoyl iodide 77 can be used as a ketone synthon and reacts smoothly with acrylate to give 78, which is hydrolyzed to give an unsaturated ketone 79[78],... [Pg.140]

The Pd(0)-catalyzed rearrangement of the iV-allylenamine 800 in CF3CO2H affords the (5, -unsaturated imine 801, which is hydrolyzed to give the 7, 8-unsaturated aldehyde 802[498]. The vinyloxaspirohexane 803 undergoes rearrangement-ring expansion to give the cyclopentanone 804 in the presence of 1 equiv. of p-nitrophenol[499]. [Pg.400]

The formation of 2.6-octadienol (27) by the reaction of 1,3-butadiene with water has attracted attention as a novel method for the commercial production of n-octanol, which has a considerable market. However, the reaction of water under the usual conditions is very sluggish. The addition of CO2 facilitates the telomerizdtion of water and 2,6-octadienol (27) is obtained as a major pro-duct[31]. In the absence of CO2, only 1,3,7-octatriene (7) is formed. Probably octadienyl carbonate is formed, which is easily hydrolyzed to give 27. A com-... [Pg.427]


See other pages where Hydrolyzates is mentioned: [Pg.191]    [Pg.2669]    [Pg.65]    [Pg.66]    [Pg.79]    [Pg.51]    [Pg.109]    [Pg.113]    [Pg.114]    [Pg.115]    [Pg.195]    [Pg.196]    [Pg.196]    [Pg.201]    [Pg.234]    [Pg.239]    [Pg.246]    [Pg.1]    [Pg.124]    [Pg.163]    [Pg.182]    [Pg.22]    [Pg.77]    [Pg.79]    [Pg.217]    [Pg.267]    [Pg.312]    [Pg.335]    [Pg.69]    [Pg.303]    [Pg.380]    [Pg.381]    [Pg.393]    [Pg.69]   
See also in sourсe #XX -- [ Pg.164 , Pg.167 ]




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Hydrolyzability

Hydrolyze

Hydrolyzed

Hydrolyzer

Hydrolyzing

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