Microcrystalline, production

Nitsche (242) grew single crystals of Hg3Te2l2 up to 4 x 4 x 4 mm in size by sublimation of the microcrystalline product, containing an excess of Te, in a sealed ampoule at 550°C. Within 10 days, crystals were formed at the colder (530°C) part of the ampoule. 

The complexation of tri- and tetrametaphosphimate ions (124-127) by group III, rare earth (88, 89, 128), and transition metals (125) was studied by Rozanov et al. and led to a vast number of new compounds. These were mostly obtained as amorphous or microcrystalline products, and they have not been characterized in detail by X-ray structure analyses. 

Upon addition of water, the hydration reactions initiate, and the hydraulic cement begins to gain strength. This process is very complex, but the strengthening effect is due basically to the formation of three types of hydration products colloidal products such as C2S xH20, which have a size of less than 0.1 p.m submicrocrystalline products such as Ca(OH)2, Al +, Fe +, and S04 phases with sizes from 0.1 to 1 tim and microcrystalline products, primarily of Ca(OH)2, with particle sizes greater than 1 p,m. The most common type of hydraulic cement, Portland cement, usually contains mostly colloidal products. 

Under the argon atmosphere, a solution of hydrated ruthenium trichloride (approximately RuCl3 3H20, containing 38-39% Ru) (1.00 g, approximately 3.83 mmol) in 50 mL of ethanol was treated with 5 mL of y-terpinene and heated under reflux in a 100-mL, round-bottomed flask for 4h. The hot solution was filtered as quickly as possible to remove the undissolved dark residue. The filtrate was concentrated to 25 mL under reduced pressure and cooled to room temperature and the red-brown microcrystalline product that resulted was collected by filtration. After drying in vacuo (approximately 1 mmHg) for 4 h, 0.70 g (59.9 %) of ruthenium complex was obtained. 

The reaction of ZrCl4 with Al(SePh)3 in ether-benzene yields the phenylselenolate Zr(SePh)4 as a turquoise, microcrystalline product.499... 

After the mixture has been cooled to o°, the ammonium i,2-naphthoquinone-4-sulfonate is collected on a 20-cm. Buchner funnel and as much of the mother liquor is removed as possible by pressing the cake with a porcelain spatula or glass stopper. The product is washed with three equal portions of a cold mixture of 150 cc. of saturated ammonium chloride solution and 100 cc. of water. The wash solution is removed as completely as possible and the product washed twice with 50-cc. portions of alcohol, followed by 300 cc. of ether in small portions (Note 5). The ammonium i,2-naphthoquinone-4-sulfonate is spread out in a thin layer and dried to constant weight at 35-40°. An orange, microcrystalline product of bright appearance is thus obtained. The yield is 350-365 g. (94-98 per cent of the theoretical amount). The ammonium salt is of good quality and is sufficiently pure for many purposes. No satisfactory method has been devised for its further purification, but it can be converted into a pure potassium salt as follows. 

Compounds from Pyrocatechol, Resorcinol and Quinol.—These three phenols yield compounds of the type (C6H5)4Cr.O.C6H4OH. C6H4(OH)2 the pyrocatechol derivative consists of orange columns, M.pt. 153 5° C., the resorcinol compound is a microcrystalline product, M.pt. 180° to 181° C., and the quinol compound forms yellow needles, decomposing at 206° C. 

In an attempt to maximize interactions between the metal dithiolene anions, Underhill and Ahmad studied the lithium salt of the [Pt S2C2(CN)2 2] cation.121,122 Slow aerial oxidation of a 50% aqueous acetone solution of H2[Pt S2C2(CN)2 2] and LiCl yielded a black microcrystalline product of small shining black needles and black platelets. Four-probe DC conduction studies on the needle-shaped crystals showed the room temperature conductivity along the needle axis to be 100 Q i cm-1. 

After cooling the reaction mixture in an ice-bath, the inorganic salts were removed by filtration and washed with acetone. The combined filtrates were concentrated in vacuo. The residual syrup was diluted with saturated brine and extracted with three portions of diethyl ether. The gathered extracts were dried over anhydrous magnesium sulfate, clarified with charcoal and treated with ethereal hydrogen chloride until precipitation was complete. The solid was slurried in diethyl ether and decanted several times, filtered and air-dried to give 3.8 g (86%) of tan 4-(2-di-n-propylaminoethyl)-7-(l-phenyl-lH-tetrazol-5-yloxy)-2(3H)-indolone hydrochloride. Recrystallization from 200 cc of hot acetonitrile gave 2.6 g (59%) of microcrystalline product, m.p. 245°C. 

In this experiment, crystalline 27 releases SO2, yielding crystalline 26 (when a single crystal of 27 was exposed to air, 26 was obtained as a microcrystalline product however, this was no longer suitable for a single-crystal X-ray analysis). 

The metathesis reaction of one equivalent of the dilithiated ethylenediamine with ZrCl4-2THF forms the monocyclic complex 13 (Scheme 6). Fractional crystallization from cold hexane affords a colorless microcrystalline product in 42% yield. Treatment of two equivalents of (Me3SiN-(CH2)2-NSiMe3)Li2 with ZrCl4 2THF results in formation of complex 12. 

A solution of 2.9 g (0.024 mole) of freshly prepared o-aminobenzaldehyde in 40 mL of absolute ethanol is heated to reflux with stirring. Copper(II) nitrate trihydrate (1.45 g, 0.006 mole) in 30 mL of absolute ethanol is added. The solution immediately changes from pale yellow to red-brown. The solution is refluxed for 1 hour, cooled to room temperature, and filtered. The dark-green microcrystalline product is washed with absolute alcohol and ether before drying in vacuo over P4O10. The yield is 2.9 g (81%). Anal. Calcd. for C2gH2oN606Cu ... 

The checker (MG) obtained a 92% yield of microcrystalline product with mp 190 to 192 C. He reports the presence of a small amount of semisolid residue between the crystals. 

Five grams of heteropolyacid crystals, (Section. A) are dissolved in 2mL of water (the solution may be warmed gently until dissolution), and 1 g of rubidium chloride is dissolved in 2 mL of water. The two aqueous solutions are mixed at room temperature, and a yellow precipitate of the rubidium salt is obtained. It is recrystallized, first, from 40 mL of a lukewarm HCl solution (c = 0.25 mol L" , temp = 60°C). After cooling, a microcrystalline product is formed. It is separated and redissolved in 100 mL of HCl solution (c= 1 mol L", temp = 60°C). The yellow needles of the rubidium salt start growing slowly after 2 days at room temperature. After 6 days the yield is 12 g (42% with respect to the starting heteropolyacid). 

The crude product is isolated and initially purified by removal of solvent by rotary evaporation followed by extraction with three small washes of THF (3 X 10 mL) to remove the extremely soluble by-product, K[Lu(CgHg)2]. Final purification and removal of KCl are achieved by transfer of the crude product (- 4.3g) to a Kontes Schlenk Soxhlet extraction apparatus. The apparatus is removed from the dry box and the residue is extracted with THF (60 mL) over a 24-h period on a Schlenk line under argon. During extraction, the pure white product precipitates in the Soxhlet receiver flask. It is isolated in 50% yield (1.73 g) by vacuum filtration in the dry box. Cooling of the light yellow filtrate to — 40 °C does not yield additional microcrystalline product. In practice, it is normally discarded (by removal from the dry box and careful quenching with 2-propanol) since it contains K[Lu(CgHg)2], which has not been removed by the previous purification step. 

In a 600-mL beaker, 30.0 g of n-Bu4NI (81.2 mmol) is dissolved in 400 mL of absolute ethanol that is purged with Ar for 15 min. Then 4.4 mL of Br2 (85.9 mmol) is added dropwise at room temperature and the color of the solution turns deep red. By the end of the bromine addition, an orange-colored microcrystalline product precipitates. The reaction mixture is brought to about 65°C for 15 min to remove excess bromine and to dissolve all precipitates, and is then slowly cooled to ambient temperature. The crude product seperates and is recrystallized twice from absolute ethanol to give 36.5 g of M-Bu4N[IBr2] (69.0 mmol, 85% yield). 

Nitrosyl(1,4,8,11-tetrathiacyclotetradecane)rhodium(III) Tetra-FLUOROBORATE, [Rh(TTP)NO] (BF4)o. To a solution of 0.25 g [Rh(TTP)]-BF4 in 40 ml acetonitrile, a solution of 0.1 g (excess) nitrosonium tetra-fluoroborate (Aldrich) dissolved in 5 ml acetonitrile was added drop-wise. During the addition, the solution turned from the golden color of [Rh(TTP)] to a bright green. The volume of the solution was then reduced to approximately 10-15 ml, and small aliquots of diethyl ether were added for 30 min. The bright green microcrystalline product was collected, washed with diethyl ether, and dried by pumping on a vacuum line. 

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