Thallous hydroxide

Thallium reacts with water containing oxygen to form thallous hydroxide, TlOH, which is a relatively strong base, absorbing carbon dioxide and attacking glass. 

Thallium oxide also can he prepared hy thermal dissociation of thallium hydroxide, TlOH or thallium carbonate, TI2CO3. Thallium oxide dissolves in water forming thallous hydroxide, TlOH. It reacts with carbon dioxide to form thallous carbonate, TI2CO3. 

There is no evidence for the existence of thallic hydroxide addition of hydroxide to an aqueous solution of a T1(III) salt gives TLO, instead. Thallous hydroxide can be isolated as yellow needles by the hydrolysis of thallous ethoxide [20398-06-5], which is conveniendy prepared as a heavy oil by the oxygen oxidation of thallium metal in ethanol vapor. Thallous hydroxide darkens at room temperature and decomposes to T O and H20 on warming. 

C. F. Rammelsberg24 obtained a pale-brown insoluble thallic periodate, 3Tl203.I207.30H20, by the action of periodic acid on thallic oxide, Tl2Oa. The compound is decomposed by potash lye thallous periodate has not been made. A yellowish-white precipitate is formed when thallous hydroxide is treated with periodic acid, or when sodium dimesoperiodate is added to the soln. of a thallous salt. The precipitate is reddish-yellow when dried, and appears to be a mixture of thallous and thallic iodates. 

Thallous hydroxide [12026-06-1] M 221.4. Crystd from hot water (0.6ml/g) by cooling. 

Refs 2 4). Thallous 2,4,6-Trinitrobenzoate, T1(C7H2N308), cryst ppt, mp l60-3°(dec) was prepd from 2,4,6-TNBAc and thallous hydroxide in boiling pyridine soln, the salt decarboxylates smoothly to 1,3,5-TNB and thallous oxalate. The... 

If the soln. be allowed to crystallize at ordinary temp., thallic azide, if it is formed at all, is decomposed with the escape of hydrazoic acid, and the precipitation of thallic hydroxide. Warm water likewise decomposes thallosothallic azide into thallic and thallous hydroxides. 

Purves and Hudson96 methylated crystalline methyl a-D-fructo-furanoside with methyl iodide-thallous hydroxide and found that one treatment with these reagents resulted in a sirup with analysis correspondent)) F. Hartley and W. H. Linnell, Quart. J. Pharm. Pharmacol., 12, 743 (1939). 

Thallous Chromate, Tl2Gr04, is precipitated when a solution of a thallous salt is mixed with potassium chromate. It is also produced by adding thallous hydroxide or carbonate to aqueous chromic acid, or by the action of ammonia on the dichromate. Thallous chromate is a yeUow crystalline powder, very sparingly soluble in water, 100 grams of which dissolve 0-03 gram of the salt at 60° C., and 0-2 gram at 100° C. ... 

Thallous hydroxide or thallous salts in the presence of alkali react with cyclopentadiene to yield TlCsHs (129). This substance, which is stable in air, crystallizes at 0° in colorless needles (in pale yellow needles at 60°), and is practically insoluble in water it is, however, moderately soluble in methanol, acetone, pyridine, etc. It does not melt when heated, but it sublimes at 100° in a high vacuum 81). 

Hydrolysis and addition of water to the double bond occurs when a-thebaizone is heated with concentrated hydrochloric acid at 95-98° C. for one hour, the product being hydroxydihydrothebaizonic acid in the aldehyde hydrate lactone form [xxn], which is converted to the free acjd [xxm] by methanolic sodium methoxide hydrolysis with thallous hydroxide affords a compound C18H2307N containing an additional molecule of water [112]. 

Hofmann degradation of a-thebaizone and its derivatives by thallous hydroxide proceeds as follows [112] ... 

The solubility of the starting material has governed the choice of the methylating agent, and has prompted some modifications of the classical procedures for example, the use of dimethyl sulfate plus sodium hydroxide in dioxane solution, and of methyl iodide plus silver oxide in A ",iV-dimethylformamide. Limited trials of newer reagents, notably those using liquid ammonia with an alkali metal plus methyl iodide, or thallous hydroxide plus dimethyl sulfate, were not encouraging. ... 

Other starch varieties chemically bind metal atoms only to the hydroxyl groups, in the same manner as alcoholates. Alkali metal starchates were obtained for the first time by the use of either metal amides in liquid ammonia641 or metals in liquid amines.642 These methods were subsequently used by others.643 Sodium 2-starchate could be prepared by refluxing an alcohol solution of NaOH and dry starch.644 The reaction of dry starch with controlled amount of NaOH in 1-butanol provided either monosodium 2-starchate or disodium 2,3-starchate.645,646 However, complexes of NaOH with starch were also characterized.37,38 Thallation of starch could be performed with thallous hydroxide.647... 

The thallium(1) ion, Tl+, behaves in certain respects as an alkali-metal ion (although in others more like Ag+). Its ionic radius (1.54 A) is comparable to that of Rb+, although it is more polarizable. Thus thallous hydroxide is a water-soluble, strong base, which absorbs carbon dioxide from the air to form the carbonate. The sulfate and some other salts are isomorphous with the alkali-metal salts. 

Spectroscopy has been used widely in investigating ion association, although it seems applicable only in cases where there is some orbital overlap of the associating ions. There are several systems where only electrostatic interaction is postulated and there are no detectable deviations from Beer s Law, but other evidence shows the occurrence of association. Examples of such systems are sodium and potassium tetra-phenylborate, thallous hydroxide and various tetralkylammonium halides. ... 

Thallium salts of glycosides, made by treatment of glycosides with aqueous thallous hydroxide, react with methyl iodide to give methyl ethers 18),... 

Colorless water-soluble thallous hydroxide 3delds brown insoluble thallic hydroxide with hypohalogenite ... 

Solutions of Chloramine T have no effect on thallous hydroxide. The same holds for the tests described in (2). 

---