Author: Ethan Frank

Synthesis of Si OCH3 4 1642 gm of crude product prepared in Example 3 was added to the distilling flask and heated slowly. Distillation fractions were collected at the head temperatures shown in Table 4 . From the composition of the fractions, the 1642 gm of crude product afforded 660 gm trimethoxysilane, which is more than that calculable from the composition of the starting material (first row of Table 4). The additional tri-methoxy silane was formed via the disproportionation of the mixed dimethylaminomethoxysilanes,. The vapor phase methanolysis consumed 2521 gm tris(dimethylamino)silane and 1005 gm methanol and produced a total of…

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Preparation of Lead Chloride / Lead ii Chloride Lead Chloride / Lead ii Chloride: 15 g of neutral lead acetate 3-hydrate are dissolved in 100ml of water and the solution made faintly acid to litmus with glacial acetic acid added dropwise. Filter if necessary and mix with a solution of 3.5g of sodium chloride in 25ml of water. The precipitation must be performed in the cold due to the solubility of the precipitated lead chloride in hot water. When the product has settled well, suction filter and wash the material thoroughly with alcohol (three 20-ml portions to facilitate drying) after draining…

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Preparation of N,N- Dimethylaniline Dimethylaniline: A mixture of 75 g of aniline, 25 g of aniline hydrochloride and 75 g of methyl alcohol is heated in an autoclave for 7-8  hours at 230-240° C, the crude reaction product then made alkaline with sodium hydroxide and distilled with water steam. The distilled oil is separated with a separating funnel, dried with solid KOH and fractionated. The fraction boiling at 190-200° is collected yielding N,N-dimethylaniline with boiling point 192° C. The Synthetic Dyestuffs and the Intermediate Products from which They are Derived, by J. C. Cain, 204-205, 1905 By slightly modified method 93…

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Synthesis of Sodium Ethoxide A solution of sodium ethoxide was prepared by adding freshly cut sodium (2.72 g, 118 mmoles) to absolute ethanol (350 ml). Guanidine hydrochloride (11.3 g, 118 mmoles) was added and the mixture was stirred and heated to reflux under a nitrogen atmosphere. A solution of ethyl 7-bromo-3,4-dihydro-2-hydroxy-1-naphthoate (11.72 g, 39.4 mmoles) in absolute ethanol (75 ml) was added dropwise over 2.5 hours. Refluxing was continued for an additional 21.5 hours, after which time the mixture was cooled to room temperature and filtered. Ethanol was evaporated under reduced pressure to give a yellow-colored foam which was dissolved…

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Preparation of benzyl bromide Benzyl bromide, as in case with benzyl chloride, is prepared by action of bromine on toluene. To the perfectly dry round bottom flask fitted with a reflux condenser, stirrer and dropping funnel 50 g toluene are placed. As the reaction flask is exposed to direct sunlight (or 500W photolamp) 75 g elemental bromine are slowly added with vigorous stirring. As the reaction proceeds the solution, which is first colored reddish-brown, becomes colorless. When all the bromine has been added, benzyl bromide is fractionally distilled and the fraction boiling between 190-205° C. collected separately. This fraction is…

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Preparation of phenylmagnesium bromide Phenylmagnesium Bromide: The formation of the Grignard reagent from bromobenzene and magnesium in ether, is difficult from the experimental point of view. For the preparation of phenylmagnesium bromide is necessary to follow the directions carefully, particularly in the matter of using completely dry reagents and dry apparatus. The provided description is used for the preparation of 0.15 mol phenylmagnesium bromide solution in ether. The phenylmagnesium bromide is prepared in a 250 ml two-necked round-bottomed flask, fitted with an efficient reflux condenser connected with a calcium chloride drying tube and dropping funnel, which will be filled with the…

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Synthesis of Acetylferrocene Acetylferrocene: A mixture of 93.0 g (0.5 mol) of ferrocene, 250 ml of acetic anhydride and 20 ml of 85% strength phosphoric acid was heated to 100° C. for 10 minutes, then cooled and added to ice. After standing overnight, the solid residue was filtered off and washed with water. For further purification, the residue was dissolved in cyclohexane, while warming, animal charcoal/Tonsil being added. The mixture was then filtered and the filtrate was evaporated to dryness under reduced pressure. 64 g (55.4% of theory) of acetilferrocene of melting point 84°-86° C. were obtained in this manner.…

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Preparation of Benzonitrile Benzonitrile: A solution of benzenediazonium chloride is prepared by dissolving 20 ml (or 20.5 g) aniline in a mixture of 50 ml of concentrated hydrochloric acid and 50 ml of water. The obtained aniline hydrochloride solution is cooled to 5° C, and then cautiously a solution of 17 g of sodium nitrite dissolved in 40 ml of water is added dropwise. During the diazotization the temperature is maintained between 5° C and 10° C. Then, while the benzene-diazonium chloride solution is standing in ice-water, 55 g of powdered copper sulfate are dissolved in 200 ml of water…

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Synthesis of Sorbitan Oleate To 1000 ml of a phosphate buffer having a pH of 7.3 were added 4.93 g of sorbitan, 22.60 g of oleic acid and 4.0 g of LIPASE MY. The mixture was incubated and processed as in Example 1 to give 18.34 g of sorbitan oleate. Similar syntheses

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Preparation of Aluminium Iodide Aluminium Iodide: Eighteen grams of iodine, heated to about 180°C are sublimed over 60 g of aluminum granules (about 10 mesh) heated at 500-625° C in vacuum or a slow stream of nitrogen or carbon dioxide. The almost white product sublimes into the receivers; a large excess of metal is used to ensure complete use of the iodine. Yield about of aluminium iodide is 75% of theory based on the iodine used. Five grams of pure aluminum are refluxed with 20 g of dry iodine in 80 ml of carbon tetrachloride until the iodine color has completely…

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