Phthalation

Succinate, benzoate, phthalate and cinnamate give buff or brownish coloured precipitates of the basic ferric salts in the cold. Add dil. H2SO4. The basic ferric succinate dissolves giving a clear solution the other basic ferric salts also dissolve, but simultaneously a white precipitate of the free acid is also formed. 

Phthalein reaction. Fuse together carefully in a dry test-tube a few crystals of phthalic acid or of a phthalate and an equal quantity of ph tol moistened with 2 drops of cone. H2SO4. Cool, dissolve in water and add NaOH solution in excess the bright red colour of phenolphthalein in alkaline solution is produced. 

As a general guide, however, it may be noted that the following have fairly easily recognisable odours methyl and ethyl formate methyl and ethyl acetate (apples) methyl and ethyl benzoate methyl salicylate (oil of winter-green) and ethyl salicylate methyl and ethyl cinnamate. (It is however usually impracticable to distinguish by odour alone between the methyl and ethyl esters of a particular acid.) Methyl and ethyl o. alate, and methyl and ethyl phthalate are almost odourless. Succinic and tartaric esters have faint odours. 

The following liquids may be used (boiling points are given in parentheses) — chlorobenzene (132-3°) bromobenzene (155°) p cymene (176°) o-dichloro-benzene (180°) aniline (184°) methyl benzoate (200°) teti-alin (207°) ethyl benzoate (212°) 1 2 4-trichlorobenzene (213°) iaopropyl benzoate (218°) methyl salicylate (223°) n-propyl benzoate (231°) diethyleneglycol (244°) n-butyl benzoate (250°) diphenyl (255°) diphenyl ether (259°) dimethyl phth ate (282°) diethyl phthalate (296°) diphenylamine (302°) benzophenone (305)° benzyl benzoate (316°). 

The commercial form of Cartesian manostat, model 7A, is depicted in Fig. II, 23, 7 it is normally charged with mercury except for very low pressures when di-w-butyl phthalate is employed. The manostat is highly sensitive in its action furthermore, once the pressure has been set in the instrument, the system may be shut down without disturbing the setting. 

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 ... 

If the perfectly anhydrous alcohols are required, the redistilled alcohol may be treated with the appropriate alkyl phthalate or succinate as already detaUed under Ethyl alcohol (5). 

Phthalic anhydride reacts similarly, but the acid phthalates are somewhat more difficult to isolate and the melting points are considerably lower. 

Successful results have been obtained (Renfrew and Chaney, 1946) with ethyl formate methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec.-butyl and iso-amyl acetat ethyleneglycol diacetate ethyl monochloro- and trichloro-acetates methyl, n-propyl, n-octyl and n-dodecyl propionates ethyl butyrate n-butyl and n-amyl valerates ethyl laurate ethyl lactate ethyl acetoacetate diethyl carbonate dimethyl and diethyl oxalates diethyl malonate diethyl adipate di-n-butyl tartrate ethyl phenylacetate methyl and ethyl benzoates methyl and ethyl salicylates diethyl and di-n-butyl phthalates. The method fails for vinyl acetate, ieri.-butyl acetate, n-octadecyl propionate, ethyl and >i-butyl stearate, phenyl, benzyl- and guaicol-acetate, methyl and ethyl cinnamate, diethyl sulphate and ethyl p-aminobenzoate. 

MC.-Octyl alcohol methyl n-hexyl carbinol CH3CH(OH)(CHj)jCH3 = CgH,OH is converted by heating with phthalic anhydride into sec.-octyl hydrogen phthalate ... 

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 ... 

Introduce 197 g. of anhydrous brucine or 215 g. of the air-dried dihydrate (4) into a warm solution of 139 g. of dZ-acc.-octyl hj drogen phthalate in 300 ml. of acetone and warm the mixture vmder reflux on a water bath until the solution is clear. Upon cooling, the brucine salt (dA, IB) separates as a crystalline solid. Filter this off on a sintered glass funnel, press it well to remove mother liquor, and wash it in the funnel with 125 ml. of acetone. Set the combined filtrate and washings (W) aside. Cover the crystals with acetone and add, slowly and with stirriug, a slight excess (to Congo red) of dilute hydrochloric acid (1 1 by volume about 60 ml.) if the solution becomes turbid before the introduction of... 

Concentrate the combined filtrate and washings (W) to about half the original volume, and pour it into sUghtly more than the calculated amount of dilute hydrochloric acid (use a mixture of 30 ml. of concentrated hydrochloric acid and 30 ml. of ice-water) then add about 300 ml. of water. Collect the active aec.-octyl hydrogen phthalate (crude lA) as above (5). The weight of the air-dried ester is about half that of the dl-ester originally used (7). 

Crystallise the two lots of crude active aec. -octyl hydrogen phthalates separately twice from 90 per cent, acetic acid use 2 g. of acetic acid to each gram of soUd. The recrystaUised esters, if optically pure (8), will melt sharply at 75° if the melting points are below 75°, further recrystallisation is necessary. The yields of optically pure products, m.p. 75°, are 48 g. and 49 g. respectively. 

The yields from the acc.-octyl hydrogen phthalates are almost quantitative. Notes. 

The inactive aec.-octyl hydrogen phthalate may be recrystallised from light petroleum, b.p. 60-80°, or from glacial acetic acid, and then melts at 55°. 

Dlnltro-benzoate p-NItro- benzoate Phenyl- urethane a-Naph- thyl- urethane Hydrogen 3-nltro- phthalate Other Derivatives... 

Indanedioiie (III) may also be prepared by condensation of diethyl phthalate (V) with ethyl acetate in the presence of sodium ethoxide the resulting sodium 1 3-indanedione-2-carboxylic ester (VI) upon warming with sulphuric acid yields (HI). 

---