Agents sodium acetate

Complexing agents, which act as buffers to help control the pH and maintain control over the free metal—salt ions available to the solution and hence the ion concentration, include citric acid, sodium citrate, and sodium acetate potassium tartrate ammonium chloride. Stabilizers, which act as catalytic inhibitors that retard the spontaneous decomposition of the bath, include fluoride compounds thiourea, sodium cyanide, and urea. Stabilizers are typically not present in amounts exceeding 10 ppm. The pH of the bath is adjusted. 

With Phenols. The 2-hydroxylethyl aryl ethers are prepared from the reaction of ethylene oxide with phenols at elevated temperatures and pressures (78,79). 2-Phenoxyethyl alcohol is a perfume fixative. The water-soluble alkylphenol ethers of the higher poly(ethylene glycol)s are important surface-active agents. They are made by adding ethylene oxide to the alkylphenol at ca 200°C and 200—250 kPa (>2 atm), using sodium acetate or... 

It is essential to neutralize any strong acid present before distilling lactic esters otherwise, condensation by ester interchange occurs, with liberation of alcohol and production of polylactic acid, a linear polyester. Other neutralizing agents, such as alkali or alkaline-earth hydroxides or carbonates, doubtless could be used satisfactorily instead of sodium acetate. 

Condensation of an appropriately substituted phenylacetic acid with phthalic anhydride in the presence of sodium acetate leads to aldol-like reaction of the methylene group on the acid with the carbonyl on the anhydride. Dehydration followed by decarboxylation of the intermediate affords the methylenephthal-ides (12). Treatment of the phthalides with base affords directly the indandiones, probably via an intermediate formally derived from the keto-acid anion (13). The first agent of this class to be introduced was phenindandione (14) this was followed by anisindandione (1S) and chlorindandione (16). ... 

Indazoles can be considered as either azaindoles or azaisoindoles depending on the reader s prejudice. Benzydamine (54) represents a drug with this heterocyclic nucleus. Alkylation of the amine of anthranilic acid methyl ester with benzyl chloride in the presence of sodium acetate gives 52. Treatment with nitrous acid leads to the nitrosoamine, which cyclizes spontaneously to the 3-ketoindazole system, 53. This intermediate forms an ether of its enol form on heating the sodium salt with 3-dimethylaminopropyl chloride. There is thus obtained benzydamine (54), a fairly potent nonsteroidal antiinflammatory agent with significant antipyretic and analgesic properties. 

By the interaction of the alcohols and acids at an elevated temperature the reaction is assisted by the use of some catalytic agent, or one which absorbs the water formed, such as dry sodium acetate. The reaction is rarely complete, however, and may be rendered more nearly quantitative by using the acid anhydride in place of the acid itself. The reaction is —... 

Reduction of 16-keto-17(0i)-hydroxyestratrienol-3-methyl to 16,17-dihydroxyestratrienol-3-methyl ether A solution of 800 mg of the alpha ketol methyl ether in 100 cc of ethanol and 10 cc of acetic acid was carefully maintained at 40°C (water bath), and 200 g of freshly prepared sodium amalgam (2%) were added in small pieces with efficient swirling. Before all of the amalgam had been added, a precipitation of sodium acetate occurred, and at this point an additional 100 cc of 50% acetic acid were added. After all the reducing agent had been added, the mixture was transferred to a separatory funnel with ether and water. 

Acetoxylation is found to accompany nitration of fairly reactive aromatics by nitric acid in acetic anhydride and gives rise to zeroth-order kinetics76. The electrophile is believed to be protonated acetyl nitrate the formation of which is rate-determining, hence the kinetic order (see p. 37). Acetoxylation can also accompany halogenation by positive halogenating agents in acetic acid solvent, especially in the presence of sodium acetate137, but no kinetic studies have been carried out. 

The reaction of 1,4-benzenediols with an equimolar amount of BTMA Br3 in dichloromethane in the presence of aq. sodium acetate at room temperature gave 2,5-cyclohexadiene-l,4-diones in good yields. On the other hand, the reaction of 1,4-benzenediols with a large excess of the agent in aq. acetic acid at 40-60°C gave polybromo-substituted products (Fig. 25) (ref. 33). 

These reagents are required for proper color development. Hydroxylamine hydrochloride is a reducing agent, which is required to keep the iron in the +2 state. The o-phenanthroline is a ligand that reacts with Fe2+ to form an orange-colored complex ion. This ion is the absorbing species. In addition, since the reaction is pH dependent, sodium acetate is needed for buffering at the optimum pH. 

Phenyl cinnamate and other phenolic esters have been prepared by heating the acid and phenol in the presence of phosphorus oxychloride,1 and by heating the acid anhydride and phenol together in the presence of a dehydrating agent such as fused zinc chloride or anhydrous sodium acetate.2 Phenyl cinnamate has also been prepared by the careful distillation of phenyl fumarate.3... 

Von Runge and Triebs used a solution of dinitrogen pentoxide in chloroform for the N-nitration of both amides and imides. Solutions of dinitrogen pentoxide in chlorinated solvents are not neutral nitrating agents when amides and imides are nitrated - the presence of acidic N-H protons in these substrates leads to the formation of nitric acid. Sodium fluoride acts like a base towards nitric acid and so its addition to these reactions can increase product yield. Sodium acetate has been used for the same purpose during the nitration of n-butyl-V, V -dimethylurea. The effectiveness of dinitrogen pentoxide for the V-nitration of ureas is further illustrated by its use in the conversion of 2-imidazolidinone to N, V -dinitro-2-imidazolidinone in 90 % yield. In the presence of sodium fluoride the yield for this reaction exceeds 90 %. 

Sodium acetate is a mordant in dyeing. Other applications are in photography, as an additive to food, in purification of glucose, in preservation of meat, in tanning, and as a dehydrating agent. In analytical chemistry it is used to prepare buffer solution. 

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