Green mixture preparation

A 500-ml three-necked flask fitted with a mechanical stirrer and a nitrogen inlet and outlet is charged with 30 g (approx. 0.055 mole) of hydrated chromium (III) sulfate, 200 ml of distilled water, 7.5 g (0.12 g-atom) of mossy zinc, and 0.4 ml (5.4 g, 0.03 g-atom) of mercury. The flask is flushed with nitrogen for 30 minutes and a nitrogen atmosphere is maintained. The mixture is then heated to about 80° with stirring for 30 minutes to initiate reaction. Then the mixture is stirred at room temperature for an additional 30 hours, by which time the green mixture has been converted to a clear blue solution. Solutions prepared as above are about 0.55 M in chromium (II) and are indefinitely stable if protected from oxygen. 

Tetraphenyltellurophene To a suspension of 1,4-dilithiotetraphenyl-l,3-butadiene in 100 mL of ether, prepared from 10 g (56 mmol) of diphenyl acetylene and excess of lithium, is added over 15 min a solution of TeCl4 (5.3 g, 19.7 mmol). The green mixture is poured into a mixture of CH2CI2 and water, the organic phase is separated, filtered through anhydrous MgS04, filtered and evaporated. The residue is recrystallized from dichloromethane/ethanol, giving tetraphenyltellurophene 5.35 g (56%), m.p. 239°C. 

In general, methods for the large-scale production of advanced materials by combustion synthesis consist of three main steps (1) preparation of the green mixture, (2) high-temperature synthesis, and (3) postsynthesis treatment. A schematic diagram of these steps is presented in Fig. 4. The first step is similar to... 

Ferric ammonium citrate [1185-57-5]—A mixture of complex chelates prepared by the iateraction of ferric hydroxide with citric acid ia the presence of ammonia. The chelates occur ia brown and green forms, are dehquescent ia air, and are reducible by light. 

A dicarbocyanine dye, dithiazinine (79), is used as a broad-spectrum anthelmentic agent, although, interestingly, it seems to have been prepared initially for use in photographic emulsions. It is made by heating 2-methylbenzothiazole ethiodide (77) with the malondialdehyde equivalent, B(ethylmercapto)-acrolein diethylacetal (78) in the presence of pyridine. There apparently ensues a sequence of addition-elimination reactions quenching the reaction mixture with potassium iodide solution results in separation of green crystals of dithiazanine iodide (79). ... 

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