Sulphates, acid

Quinidine is alkaline in solution and behaves as a diacidic base forming two series of salts. The neutral sulphate, Bj. H2SO4.2HjO, crystallises from hot water in colourless prisms, soluble in water (1 in 98 to 100 at 15°, or 1 in 7 at 100°), more so in alcohol or chloroform, and scarcely in ether. It is dextrorotatory, [a]D +184-17° (CHCI3). The acid sulphate, B. H2SO4.4H2O, forms hair-like, colourless needles, soluble in 8-7 parts of water at 10° + 247-8° (c = M/10, HjO) or + 256-4° (c = M/40,... 

Of more direct interest is the preparation of 3-ethylquinuclidine by this method (Prelog, Sogtaric and Gustak (1940)). Ethyl tetrahydropyranyl ketone (X R = tetrahydropyranyl in X to XIV) was condensed wiA ethyl brpmoacetate (XI) to give the hydroxy-acid ester (XII) which was dehydrated by potassium acid sulphate at 90° to ethyl 3-(tetrahydro-pyranyl-4)-pentenate (XIII) and this hydrogenated to tie corresponding... 

Sinapine, CjgHjjOgN, was isolated as a thiocyanate from black mustard seeds (Brassica nigra) by Henry and Garot." Will and Laubenheimer first noted that sinapine occurs in white mustard seed in the form of the alkaloidal glucoside sinalbine, CajH jOuNgSg, which, on hydrolysis by the enzyme myrosin, also present in the seed, furnished dextrose, p-hydroxybenzylthiocarbimide and sinapine sulphate. Owing to its instability sinapine is unknown in the free state. The thiocyanate can be recrystallised from water and converted into the acid sulphate by treatment with sulphuric acid. 

Sinapine acid sulphate, CjgH240jN. HSO4. SHjO, crystallises in leaflets, m.p. 127° (188°, dry). The thiocyanate, CigHj OjN. SCN. HjO, forms pale yellow needles, m.p. 178° iodide, m.p. 185-6°. When the thiocyanate is warmed with alkalis there is formed choline and sinapic acid, the acid was investigated by Remsen and Coale, and... 

HjO) and Bj. H2SO4.4HjO, m.p. 203-4°, [a] ° + 120° the acid sulphate, B. HjSO, occurs in yellow prismatic needles, m.p. 246-8° (corr., dec.), [a]n + 113-1° (HjO) the hydrochloride forms yellow, pentagonal plates, m.p. 286° (corr., dec.), and shows a purple fluorescence in solution in alcohol the picrate separates from alcohol in rosettes of reddish-orange needles, m.p. 194-5° (cort.). Dilute solutions of the salts are yellow and show a marked blue fluorescence. Alstonine behaves as a monoacidic base, contains one methoxyl but no methylimino group, and, unlike echitamine, does not give indole colour reactions. 

Aggressive environments include marine conditions and particularly industrial atmospheres containing high concentrations of acid gases such as sulphur dioxide rain washing is benehcial in both environments, while dampness and condensation alone can accentuate the rate of attack in the presence of chlorides and acidic sulphates. 

The combination of acidic sulphates and condensation experienced in some industrial conditions, can cause a particularly voluminous loose corrosion product on some alloys, such as NS3. Where this is likely to be... 

Legislation enacted by both Canada and the United States (see the US-Canada Air Quality Accord, 1991) will, when implemented, reduce the North American emissions of sulphur dioxide by about 50% based upon the 1980 baseline. These projected emission fields have been appplied in the atmospheric source-receptor models that were described above, to provide a projected deposition field for acidic sulphate that would be expected (14). The predicted sulphate deposition fields have then subsequently been appUed in aquatic effects models that provide estimates of regional surface water acidification distributions (50). The regional acidification profiles have then been used in a model of fish species richness (51) that results in an estimate of the expected presence of fish species as compared to that expected in an unacidified case. 

Penneman et al., have studied these reactions in acidic sulphate, nitrate and perchlorate media, and have found that only in sulphate media is the latter step relatively important. The disproportionation reaction rate coefficient has been estimated as > 1.03x10 l.mole .sec at 0 °C (mediaS x 10 Afin HNO3). 

Gena, K., Mizuta, T., Ishiyama, D. and Urabe, T. (2001) Acid-sulphate type alteration and mineralization in the Desmos Caldera, Manus Back-arc Basin, Papua New Guinea. Resource Geology, 51, 31 14. 

On a technical scale aniline is heated with one mole only of H2S04, i.e. as acid sulphate the temperature is about the same as that given above. (The baking process.) Compare this process, which can also be used in the laboratory, with that here described. 

Drake [35] has measured the thickness of the diffusion layer during the electrodeposition of copper from an acidic-sulphate system. He obtained a value of approximately 200 pm for the silent system and values of 34 pm and 3.4 pm for ultrasonic frequencies of 1.2 MHz and 20 kHz respectively. The corresponding values of the limiting-current density were from 8 Am (silent) to 50 A m (1.2 MHz) to 500 A m (20 kHz), indicating a significant increase in the rate of deposition. 

Dent D. 1986. Acid Sulphate Soils A Baseline for Research and Development. Wagenin-gen International Institute for Land Reclamation and Improvement. 

The unit cell dimensions and the space-group of biguanide acid sulphate are (440) a 11.507 b 20.446 c 7.203 A. and Pbca. Data are also available for ruthenium biguanide sulphate (287) and copper biguanide chloride (288). 

Phthalate/sulphate 1 Chelidamic acid/sulphate J Ali Dzombak, 1996... 

Lepidocrocite transforms to goethite in acid sulphate solution (Krause et al.,... 

Fanning, D.S. Burch, S.N. (1997) Acid sulphate soils and some associated environmental problems. Adv. Geoecology 30 145-158... 

---