Dehydration alcohols and

The possibility of an attack by the drying agent on the compound to be dried must always be considered carefully and if necessary examined by small-scale tests, as has been mentioned before. Most notable for such unwanted aggression amongst the popular drying agents is the molecular sieve. Various grades of molecular sieve have different activities and specialist publications should be consulted for details. The main reactions which must be kept in mind are that they can catalyse the dehydrochlorination of alkyl chlorides and the condensation of ketones, they can dehydrate alcohols and can form exposive compounds from nitroalkanes (see Section 4.6.3.). 

Diluent Dissolve 7.6 g of sodium borate decahydrate in about 800 ml of water. Add 1 g of edetate disodium, and adjust with 50% sodium hydroxide solution to a pH of 11 0.1. Transfer the solution to a 2000-ml volumetric flask, add 400 ml of dehydrated alcohol, and dilute with water to volume. 

Ciprofloxacin is practically insoluble in water, very slightly soluble in dehydrated alcohol and in dichloromethane, and soluble in dilute acetic acid [3],... 

Lemon Oil, Coldpressed, occurs as a pale to deep yellow or green-yellow liquid with the characteristic odor and taste of the outer part of fresh lemon peel. It is the volatile oil obtained by expression, without the aid of heat, from the fresh peel of the fruit of Citrus limon L. Burmann filius (Fam. Rutaceae) with or without the previous separation of the pulp and the peel. It is miscible with dehydrated alcohol and with glacial acetic acid. It may contain a suitable antioxidant. 

Fam. Rutaceae). It is miscible with dehydrated alcohol and with carbon disulfide. It is soluble in glacial acetic acid. It may contain a suitable antioxidant. 

Rosin Dissolve 2 g of sample in 10 mL of dehydrated alcohol, and add slowly, with shaking, 50 mL of solvent hexane. Transfer the solution to a separator, wash with two 50-mL portions of water, and discard the washings. Filter the solvent layer, evaporate it to dryness, and add 2 mL of 1 2 (v/v) liquefied phenohmethylene chloride to its residue. Stir, and transfer a portion of the mixture to a cavity of a color-reaction plate. Fill an adjacent cavity with 1 4 (v/v) bromine methylene chloride, and cover both cavities with an inverted watch glass. No purple or deep indigo blue color appears in or above the liquid containing the sample residue. 

Standard Solutions. Dissolve 1 g of paracetamol in the minimum volume of dehydrated alcohol, and dilute to 100 ml with water to give a stock solution containing 10 mg/ml. This solution should be stored frozen. To 20-ml aliquots of normal plasma add 100, 200, 400, 600, and 800 ll1 of the stock solution to give standard solutions containing 50,100,200,300, and 400 LLg/ml of paracetamol. Note that paracetamol is unstable in plasma fresh plasma standards should be prepared each week and stored at 4° when not in use. 

Soluble 1 in 200 of water miscible with dehydrated alcohol and ether. 

Practically insoluble in water, dehydrated alcohol, and ether soluble 1 in 122 of ethanol (80%) and 1 in 4 of pyridine slightly soluble in chloroform freely soluble in a mixture of equal volumes of chloroform and methanol. 

Soluble 1 in 4150 of water, 1 in 66 of dehydrated alcohol, and 1 in 6250 of ether sparingly soluble in ethanol practically insoluble in chloroform soluble in dilute acids and alkalis. 

Practically insoluble in water slightly soluble in dehydrated alcohol and chloroform sparingly soluble in methanol. 

A white crystalline powder. M.p. about 235°, with decomposition. Practically insoluble in water soluble 1 in 120 of ethanol, 1 in 170 of dehydrated alcohol, and I in 150 of chloroform. 

Soluble in water and chloroform freely soluble in dehydrated alcohol and methanol practically insoluble in ether. 

Soluble 1 in 1 of water and 1 in 100 of ethanol practically insoluble in dehydrated alcohol and ether soluble in methanol. 

Very slightly soluble in water soluble 1 in 150 of ethanol, 1 in 11 of acetone, and 1 in 40 of chloroform very soluble in dehydrated alcohol and methanol. 

Solubility readily soluble in a mixture of acetone and methyl or ethyl alcohol (1 1), in a mixture of methyl alcohol and dichloromethane (1 1), and in aqueous alkali. Practically insoluble in water and dehydrated alcohol and very slightly soluble in acetone. The solubilities of the HP-50 and HP-55 grades, in various solvents and solvent mixtures, are shown in Table... 

The reaction of cyclic trans-1,2-diols with DEAD and TPP generally gives the corresponding oxiranes via phosphoranes. Cyclic cis-1,2-diols also react with DEAD/TPP to afford primarily phosphoranes (26) which decompose into final product(s) such as oxiranes (with retention of configuration) (eq 21) and dehydrated alcohols and/or ketones (eq 22). ... 

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