Phthalate-sodium hydroxide

If, however, the sodium hydroxide is removed by allowing it to react with excess of an ester of high boiling point, such as ethyl succinate or ethyl phthalate, super-dry ethyl alcohol may be obtained ... 

The latter upon decomposition with dilute hydrochloric acid yields laevo sec.-octyl hydrogen phthalate the crystalline brucine salt, when similarly treated, affords the dextro sec.-octyl hydrogen phthalate. These are reerystallised and separately hydrolysed with sodium hydroxide solution to yield pure I- and d-sec.-octyl alcohols ... 

Optically pure I- and d-sec.-octyl alcohols are obtained by distillation in a current of steam of the -octyl hydrogen phthalate and 2 moles of sodium hydroxide in 30 per cent solution. The alcohols are practically insoluble in water and are separated, dried with potassium carbonate and distilled. Each boils at 86 /20 mm. and has a rotation (0)5461-1-11.8°, (a) -1-9.9° ( )546i (0)0 9-9°- The yields of alcohol from the sec.-... 

Spray solution II Dissolve 92 mg potassium hydrogen phthalate in 100 ml water and adjust the pH to 5.0 with sodium hydroxide solution (1 mol/l). Dissolve 5 g sodium perchlorate in this solution [9]. 

Potassium hydrogen phthalate Sodium perchlorate monohydrate Sodium hydroxide solution (1 mol/l)... 

A sample of a solid, weak monoprotic acid, HA, is supplied along with standard sodium hydroxide solution. The sodium hydroxide solution was standardized with potassium hydrogen phthalate (KHP). 

Materials Required Ammonium nickel sulphate (pure) 0.0135 g phthalate or acetate (ethanoate) buffer (pH 6.0) 5 ml dilute ammonia solution chloroform 15 ml sodium hydroxide (0.1 M) 10.0 ml ... 

Potassium hydrogen phthalate Potassium hydrogen phthalate Potassium iodate Anhydrous sodium carbonate Zinc metal Standardisation of sodium hydroxide solution Standardisation of acetous perchloric acid Standardisation of sodium thiosulphate solution through generation of iodine Standardisation of hydrochloric acid Standardisation of EDTA solution... 

A study of the completion of reaction vs. time was also made on the direct esterification of a typical olefin with a primary alkyl acid 0-phthalate. By titration of the reaction mass with 0.5N sodium hydroxide, we determined the rate of reaction using standard conditions of catalyst level, reaction temperature and olefin excess as previously described. The acid value reached a minimum and longer time cycles did not reduce this to any great extent. 

If perfectly anhydrous alcohols are required these may in general be obtained by treatment with sodium followed by addition of the corresponding alkyl succinate or phthalate. Sodium alone cannot be used for the complete removal of water in an alcohol owing to the equilibrium between the resulting sodium hydroxide and the alcohol ... 

The Pasteur method can also be applied to the resolution of neutral racemates, if these can be first converted into an acidic or basic derivative from which eventually a mixture of crystalline diastereoisomeric salts may be prepared by appropriate neutralisation. Thus, a racemic alcohol (e.g. ( )-octan-2-ol, Expt 5.220) may be converted into the corresponding racemic hydrogen phthalate ester by heating with phthalic anhydride, and the ester is then resolved by the Pasteur procedure using an optically active base. The resulting optically active hydrogen phthalate ester is then carefully hydrolysed with aqueous sodium hydroxide to regenerate one of the optically active forms of the alcohol. 

A. Sodium hydroxide solution 0.3125 N (12.5 g per liter sodium hydroxide reagent grade. Standardize against potassium acid phthalate). 

Figure 2. Ion chromatographic separation of a series of anions on polymer-based column with adsorbed decyl-2.2.2 using gradient capacity from sodium hydroxide to lithium hydroxide aqueous eluent. Anions 1) fluoride 2) acetate 3) chloride 4) nitrite 5) bromide 6) nitrate 7) sulfate 8) oxalate 9) chromate 10) iodide 11) phosphate 12) phthalate 13) citrate 14) thiocyanate (from refs. 13,14)...

Phthalate 5.9 5.1 g Potassium acid phthalate 0.86 g Sodium hydroxide (W20)... 

Recovery of the Active Alcohols. Each of the pure hydrogen phthalates is hydrolyzed by dissolving it in 2.5 moles of sodium hydroxide (in 20-25% solution) and distilling the mixture" with steam. The alcohol layer of the distillate is separated, dried with potassium carbonate, and distilled. Alternatively the alcohols may be taken up in about 5 volumes of pure benzene and dried by distilling the moist benzene. The active alcohols boil at 86°/20 mm. and have [a]D 9.8° (c = 5, 95% ethanol). The yield in this step is practically quantitative. 

The d-s-butyl hydrogen phthalate and the corresponding pure alcohol may be obtained from the brucine salt by the general procedure previously described for the octyl hydrogen phthalates (p. 402). Pure d-s-butyl hydrogen phthalate has [a]D + 38.5° (c = 4, 95% ethanol). Alternatively, the process may be shortened considerably by treating the brucine salt directly with a small excess of dilute sodium hydroxide and distilling the alcohol with steam.138 The alcohol is extracted or is salted out with potassium carbonate, dried, and distilled b.p. 98°/750 mm. [ ]d + 10.83° (without solvent). 

Optically active 2-butanol is prepared by converting the alcohol into the acid phthalate ester, 2.01 mol of which are thoroughly mixed with 2.0 mol of brucine. The mixture is charged into a 6-1 erlenmeyer flask with 2 1 of acetone and refluxed for 24 h. The solid changes in appearance during the reflux period and is kept broken up so that the acetone can come in contact with all of the solid. The mixture is filtered hot and recrystallized two or three times from methanol. The brucine salt is hydrolysed with sodium hydroxide to give a high purity (+)-2-butanol. 

N Sodium Hydroxide Dissolve 2.0 g of sodium hydroxide in water, and dilute to 100 mL. Standardize with NIST grade potassium hydrogen phthalate. 

Disodium hydrogen phthalate-sodium dihydrogen orthophosphate Dipotassium hydrogen phthalate-potassium dihydrogen orthophosphate Potassium dihydrogen orthophosphate-sodium hydroxide Borate buffer, phosphate buffer... 

Sodium hydroxide solution is usually standardized by titrating a pure sample of potassium hydrogen phthalate (KHP), an acid with one acidic hydrogen and a molar mass of 204.22 g. It takes 34.67 mL of a sodium hydroxide solution to titrate a 0.1082-g sample of KHP. What is the molarity of the sodium hydroxide ... 

A student titrates an unknown amount of potassium hydrogen phthalate (KHQH4O4, often abbreviated KHP) with 20.46 mL of a 0.1000 M NaOH solution. KHP (molar mass = 204.22 g/mol) has one acidic hydrogen. How many grams of KHP were titrated (reacted completely) by the sodium hydroxide solution ... 

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