Purple Powder

Titanium trichloride [7705-07-9] M 154.3, m >500 , pKj 2.55 (for hydrolysis of Ti to TiOH ). Brown purple powder that is very reactive with H2O and pyrophoric when dry. It should be manipulated in a dry box. It is soluble in CH2CI2 and tetrahydrofuran and is used as a M solution in these solvents in the ratio of 2 1, and stored under N2. It is a powerful reducing agent. [Inorg Synth 6 52 I960, Synthesis 833 7989.]... 

Deprotonation of Group 4 mono(pentamethylcyclopentadienyl) metal acet-amidinates can be achieved in high yield using sterically encumbered bases (Scheme 103) to provide anionic enolate complexes as purple powders. These can subsequently be allowed to react with electrophiles (e.g., PhCH2Cl, CH2CI2, Me2SiCl2) to produce several new classes of metal amidinates that are not accessible by conventional routes (Scheme 104). ° ... 

Another early use of iron oxides was as a cosmetic. The cosmetic boxes (cockleshells) found in the Royal Cemetery in the ancient Sumerian city of Ur contained a range of different colours. XRD analysis by the Research Department of the British Museum showed that the principal components of the red and yellow colours were hematite and goethite, respectively (Bimson, 1980). One box also contained a purple powder consisting of a mixture of quartz grains and large crystals of hematite. 

A solution prepared by dissolving 0.96 g of [Cu(tpa)(0H2)][C104]2 (1-7 mmol) in 20 mL of water is stirred, and the pH is adjusted to pH 7 using 0.5 M sodium hydroxide solution. A solution of 92 mg of K3[Fe(CN)6] (0.28 mmol) dissolved in 8 mL of water is then added dropwise to the stirred solution. This resulted in the immediate formation of a purple precipitate that was collected by filtration washed successively with cold water, ethanol, and ether and then air-dried to afford a purple powder of [ Cu(tpa)(CN) 6Fe][C104]g 3H2O (Yield 0.66 g, 74%). Small dark purple crystals suitable for X-ray structure determination were obtained by slow evaporation of a solution prepared by dissolving the purple powder in hot water. 

Compound (CHg Tel.CHgTelg6 (Vernon s j8-iodide).7—A filtered solution of the foregoing mixed anhydride is treated with hydriodic acid, the precipitate dissolved in acetone and reprecipitated by the addition of chloroform. Glistening crystals result, which are either deep purplish-red or bronzed greenish-black. Each crystal gives a reddish-purple streak, and the purple powder decomposes between 80° and 85° C. It is almost insoluble in chloroform and most non-hydroxvlie solvents. The crystals are monoclinic, the parameters being a b c =0 5465 1 0 4222 jS =76° 52. The density is 3 305 at 14° C.8... 

Dichromium tungsten(VI) oxide is a deep-purple powder possessing the trirutile type of structure. The compound crystallizes in the space group/>42/mnm. with Z = 2,a0 =4.582 A., c0 = 8.870 A. 

Titanium trichloride, as prepared by this method, is a brownish-purple powder with a bulk density varying from 0.07 to 0.25 g./cc. The particles vary in size from a few microns to aggregates of several hundred microns. The material is very reactive, being immediately hydrolyzed by moisture and pyrophoric in air. Any transfer or handling of the powder must be done in a dry box under nitrogen or an inert gas, if contamination is to be prevented. 

The trisquaternary salt (product of equation 6) is a pale purple powder which can be isolated by addition of dioxane to the ethanol-water mixture followed by filtration. In cases where the isolation of the salt is desired, better yields can be obtained by carrying out the quaternization reaction in dioxane solution. Isolation is then accomplished by addition of ethyl ether and filtration. Preliminary experiments in which laboratory animals were injected with solutions of the crude salt indicated a high degree of toxicity. 

Adsorb the crude product on alumina and apply it on a silica gel column chromatography. The column is eluted with toluene under argon pressure. Pure alcohol compound 20 (purple powder) is obtained with toluene containing 0 to 0.5% ethyl acetate as eluant. Yield 65%. 

The pure aldehyde derivative 21 is obtained as a purple powder in quantita-... 

The trans-dioxotetracyanotungstate K4[W(0)2(CN)4] 6 HjO is obtained as yellow-brown crystals by a procedure similar to that described for the Mo(IV) analog. This salt, as well as the related oxo-hydroxocomplex K3[WO(OHXCN)4] (purple powder) may also be obtained by controlled photolysis of K4[W(CN)g] in aqueous... 

Properties Dark red to purple powder. D approximately 1.50. Soluble in water, glycerol, propylene glycol insoluble in most organic solvents. 

Properties Purple powder. Mp 75C. Insoluble in water soluble in alcohol and acetone. 

The substrate-indicator solution is prepared by dissolving 8 mg bromocresol purple powder (Gurr) in 1.48 ml 10 mM sodium hydroxide and made up to 100 ml with deionized water. Urea (100 mg) and EDTA (to 0.2 mM) are then added and the pH is adjusted to 4.8. 

The product is purified by chromatography on a silica gel column (1.5 cm x 20 cm) packed with CHC13. About 0.5 g of the product is dissolved in about 5 mL of 3 1 CHCl3/MeOH and loaded on the column. The product is eluted with 96% CHCl3/4% MeOH. The first band, containing the product, is deep purple in color. A second teal-colored band elutes after the product. The purple product is collected and the solvent is removed to yield a dark purple powder. Typical yield is 40-45%. 

Hydroxide, Pr(OH), a gelatinous pale green precipitate, obtained by the action of alkali hydroxide on a soln of a praseodymium salt a purple powder when obtained by the action of water on praseodymium carbide. 

The trifluoromethanesulfonato complexes are isolated as free-flowing violet or purple powders. The yield in each case is essentially quantitative. As isolated, the products contain small amounts of [(CH3CH)20H]+[CF3S03] which maybe simply removed by boiling suspensions of the solids in chloroform. Rapid recrystallization from cold aqueous NaCF3S03 solutions is possible,2 but losses through aquation are substantial. The crude products show acceptable analytical purity and are suitable for most preparative purposes. 

Two and twenty-nine hundredths grams (0.004 mol) of red frans-pyridinium tetrachloro(dipyridine)iridate(III) is dissolved with stirring in 75 ml. of 1 aqueous ammonia contained iii a 150-ml. beaker. The solution is warmed, and a mixture of 25 ml. of nitric acid and 5 ml. of hydrochloric acid is added, whereupon a deep purple powder immediately precipitates. After the mixture has been allowed to stand at room temperature for a half-hour, the precipitate is collected by suction filtration on a small sintered-glass funnel (fine porosity), washed with 25-ml. portions of water, ethanol, and ethyl ether, air-dried, and finally dried at 110° for one hour. The yield is 1.86 g. (94.3%). Anal. Calcd. for Ir(C5H6N)2Cl4 Ir, 39.16 C, 24.39 H, 2.01 N, 5.67. Found Ir, 38.98 C, 24.36 H, 1.97 N, 5.67. ... 

When a solution of titanic acid in hydrochloric acid is acted on by zinc, a purple powder is thrown down, which is supposed to be a hydrate of the protoxide. It rapidly absorbs oxygen from the air, and is reconverted into titanic acid. 

The Mysterious and Yellow is called by some Fixed Elixir (fudan), and by others Purple Powder (zifen). 

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