Chloride separation

This is filtered off and cold concentrated sulphuric acid added, when lead(IV) chloride separates as an oily yellow liquid ... 

Method 2. The procedure described under Benzenesulphonyl Chloride, Method 2 (Section IV,206) may be used with suitable adjustment for the difierence in molecular weights between sodium p-toluenesulphonate (Section IV,30) and sodium benzenesulphonate. When the reaction product is poured on to ice, the p-toluenesulphonyl chloride separates as a sohd. This is filtered with suction it may be recrystaUised from hght petroleum (b.p. 40-60°) and then melts at 69°. 

An alternative method of purification consists in dissolving the crude sulphonyl chloride in the minimum volume of boiling chloroform, transferring rapidly to a warm separatory funnel, and separating the lower chloroform layer upon cooling the chloroform solution, the crystalline sulphonyl chloride separates, and is collected by filtration with suction. A further quantity is obtained by concentrating the mother liquor. 

Although most of the lithium chloride separates from the ether solution as a finely divided solid during the reaction, additional small quantities of lithium chloride continue to separate for 12-14 hr. After standing overnight, a typical reaction contains a precipitate of finely divided brownish-pink solid below a clear, pale yellow solution. 

In a 3-I. round-bottomed flask are placed 500 cc. (400 g., 8.7 moles) of absolute alcohol which has been saturated in the cold with hydrochloric acid gas (Note i), 870 cc. (6S0 g., 20 moles) of 96 per cent alcohol (Note 2) and 70 g. (1.03 moles) of methyleneaminoacetonitrile (Note 3). This mixture is refluxed on a steam bath for three hours (Note 4). During the refluxing, ammonium chloride separates. After the reaction is complete, the hot alcohol solution is filtered with suction and the filtrate cooled, thus allowing the glycine ester hydrochloride to separate out in fine white needles. The product is filtered with suction, sucked as dry as possible on the filter, and then allowed to dry in the air. The yield is about no g. The alcohol from the filtrate is distilled (Note 5) until about one-third of its volume is left and again cooled and a second crop of crystals is obtained. The total yield of product, m.p. 142-143, varies from 125 to 129 g. (89-91 per cent of the theoretical amount). If a very pure product is desired, it may be recrystallized from absolute alcohol. 

Aj Preparation of 5-Trifluoromethylaniline-2,4-Disulfonylchloride— H ml of chlorosulfonic acid Is cooled in an ice bath, and to the acid is added dropwise while stirring 26.6 grams of a,a,a-trifluoro-m-toluidine. 105 grams of sodium chloride is added during 1-2 hours, whereafter the temperature of the reaction mixture is raised slowly to 150°-160°C which temperature is maintained for three hours. After cooling the mixture, ice-cooled water is added, whereby 5-trifluoromethylaniline-2,4-disulfonyl chloride separates out from the mixture. 

A product consisting largely of 5-chloro-4-hydroxybenzene-1,3-disulfonyl chloride separates as a gum which solidifies on standing for about 1 hour. The solid product is collected on a Buchner funnel, washed with water and thoroughly dried in air at room temperature. 

A mixture of this crude product (approximately 302 grams, 0.92 mol) and 480 grams (2.3 mols) of phosphorus pentachloride is heated for 1 hour at 120°-140°C in a 2 liter round-bottomed flask. The resulting clear solution is poured on ice. 4,5-Dichlorobenzene-1,3-disulfonyl chloride separates immediately as a solid. It is collected by filtration and washed with water. While still moist, it is added in portions during about 20 minutes to 1 liter of concentrated ammonia water contained in a 3 liter beaker surrounded by a cold water bath. The reaction mixture is then allowed to stand for 1 hour without cooling after which it is heated on a steam bath for about 30 minutes while air is bubbled through it, in order to remove some of the excess ammonia. It is then filtered, acidified with concentrated hydrochloric acid and chilled. 

Alternative (Bl 3.6 grams (0,01 mol) prednisolone and 4.32 grams (0.012 mol) stearoyl-glycolyl-chloride, separately dissolved in dry dioxane, are added with 0.B9 ml (0.011 mol) dry pyridine. The mixture is kept at 60°C for 20 hours, then poured into water-ice and filtered. Crystallization from diluted ethanol results in prednisolone-21-stearoyl-glycolate (MP 104°-105°C). 

Water Extract with methylene chloride, separate, dry, concentrate GC/FPD 9.05 pg/L No data Fasano et al. 1982... 

The precipitated mercurous chloride separates as a sludge. In the original process, some of this mercurous chloride was chlorinated to mercuric chloride for re-use. In a later version of the process, all the mercuric chloride is electrolytically converted to elemental mercury and chlorine. As of 1994 the electrolytic version had been installed in three plants. Developed by Boliden, Sweden, and Norzink, Norway, and now offered for license by Boliden Contech. 

Reduce 3,5-dimethoxybenzoic acid with lithium aluminum hydride to 3,5-dimethoxybenzyl alcohol (I), to 10.5 g (I) in 100 ml methylene chloride at 0° C add 15 g PBr3 warm to room temperature and stir for one hour. Add a little ice water and then more methylene chloride. Separate and then dry, evaporate in vacuum the methylene chloride. Add petroleum ether to precipitate about 11.5 g of the benzyl bromide (II). To 9.25 g (II), 15 g Cul, 800 ml ether at 0° C, add butyl (or other alkyl)-Li (16% in hexane), and stir for four hours at 0° C. Add saturated NH4C1 and extract with ether. Dry and evaporate in vacuum the ether (can distill 100/0.001) to get about 4.5 g olivetol dimethyl ether (HI) or analog. Distill water from a mixture of 90 ml pyridine, 100 ml concentrated HC1 until temperature is 210° C. Cool to 140 0 C and add 4.4 g (III) reflux two hours under N2. Cool and pour into water. Extract with ether and wash with NaHC03. Make pH 7 and dry, evaporate in vacuum to get 3.8 g olivetol which can be chromatographed on 200 g silica gel (elute with CHC13) or distill (130/0.001) to purify. 

Silver chloride separation and economic recovery of silver for recycling back to the process. 

Make a solution of 4.5 g of the pyrone in 150 ml of benzene and add it dropwise to a solution of 7.8 g of clean thin strips (or ribbon) of magnesium, and 18 ml of methyl iodide in 90 ml of dry ether. Reflux for 20 hours and add 45 ml of saturated ammonium chloride. Separate the organic layer and extract the aqueous phase with the benzene. Combine the organic layer with the benzene extractions and dry. Evaporate the benzene off in vacuo to get the THC. TET, 23, 77 (1967). 

Hexammino-cobaltous Chloride, [Co(NH3)6]C12, is the most stable of the three ammines of cobaltous chloride and may be prepared in aqueous solution. If ammonia gas be passed into a concentrated aqueous solution of cobaltous chloride the greenish precipitate at first formed dissolves in excess of ammonia in absence of air, giving a red solution. From the liquid, on standing, pale red octahedral crystals of pentammino-cobaltous chloride separate. The crystals are stable in absence of air but lose ammonia if kept over sulphuric acid. On heating to 120° C. the substance loses four molecules of ammonia and is transformed into diammino-cobaltous chloride. It is soluble in aqueous ammonia without decomposition and insoluble in alcohol. With platinous chloride it forms a double salt, [Co(NH3)3]PtCl4.3 Cobaltous... 

The chloride separates in microscopic yellow needles on the addition of hydrochloric acid to the nitrate. 

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