Bromine-hydrochloric acid

Further, 6-aminopenicillanic acid reacted with bromine, hydrochloric acid and NaN02. As a result the 6,6-dibromopenicillanic acid was obtained. 

Polarographic Determination of Fluoride. Part II. The Determination of Fluoride in Bromine, Hydrochloric Acid and Hydrobromic Acid. Analyst 79, 267 (1954). 

Brominations. Hydrochloric acid is a catalyst for arene bromination in acetone. 

The hydrocarbons of the composition (CsHs) present in plants are called terpenes. The more important members of the class have the formula CioHie, and are obtained from the sap of coniferous trees and from fruits of the citrus variety they are the principal constituents of oil of turpentine and of many essential oils. With few exceptions the terpenes are liquids some are optically active. They polymerize when treated with sulphuric acid, and form addition-products with bromine, hydrochloric acid, and water. The terpenes can be converted into cymene, and like this hydrocarbon yield p-toluic acid and terephthalic acid when oxidized. 

Bromine, hydrochloric acid, sulfuric acid - 285 Bromine, methyl alcohol solution - 736, 765 Bromine pentafluoride - 356 Bromine trifluoride - 356, 824 Bromine vapor - 55, 124, 149, 185, 264, 647, 674, 731, 736, 765, 848... 

The olefin or ethylene series (type formula C H2n) is composed of unsatu rated hydrocarbons i.e., the members of this series are capable of uniting directly with other materials such as chlorine, bromine, hydrochloric acid, and sulfuric acid, without displacing a hydrogen atom. The names of these hydrocarbons end in ene, as ethene (ethylene), propene (propylene), and butene (butylene). Unsaturated compounds react with and dissolve in sulfuric acid and may thus be removed from petroleum oils. The low-boiling olefins are probably not present in crude petroleum, but they are... 

Hydrobromic acid is rather easily oxidised when exposed to light and becomes brown due to the bromine liberated. Otherwise, its properties are those of a strong acid, similar to hydrochloric acid. 

Bromination has been described using brominating agents such as N-bromosuccinimide in carbon tetrachloride (418. 420) bromine in either chloroform, acetic acid, or hydrochloric acid (414. 418, 421-423) bromine in sulfuric acid (415-417) and enzymatic catalysis (424, 425). 

Syntheses of a,)3-dihalogenoethers can be achieved in various ways the classical method (37), wherein a current of dry gaseous hydrochloric acid, is made to react in an equimolar mixture of ethanol and aldehyde at 20°C first to form the monochloroether (50% yield) and then by the action of bromine, the dibromoether (80 to 90% yield) can be used. The second and simpler method is the direct bromination of ethylvinylether in a chloroformic or dioxane solution if the product is used directly without purification,... 

Treatment of quinoline with cyanogen bromide, the von Braun reaction (17), in methanol with sodium bicarbonate produces a high yield of l-cyano-2-methoxy-l,2-dihydroquinoline [880-95-5] (5) (18). Compound (5) is quantitatively converted to 3-bromoquinoline [5332-24-1], through the intermediate (6) [66438-70-8]. These conversions are accompHshed by sequential treatment with bromine in methanol, sodium carbonate, or concentrated hydrochloric acid in methanol. Similar conditions provide high yields of 3-bromomethylquinoHnes. 

Nitration of > -hydroxyben2oic acid with filming nitric acid in the presence of sulfuric acid and acetic anhydride gives a mixture of the 2-nitro [602-00-6] and 4-nitro [619-14-7] substitution products. Bromination and iodination yield the 4-halogenated derivatives (4-bromo [14348-38-0] and 4-iodo [58123-77-6]). When > -hydroxyben2oic acid is treated with formalin in the presence of hydrochloric acid, 4-hydroxyphthahde [13161 -32-5] is obtained as shown in equation (10). 

Hydrochloric acid reacts with sulfur only in the presence of iron to form hydrogen sulfide. Sulfur dioxide forms when sulfur is heated with concentrated sulfuric acid at 200°C. Dilute nitric acid up to 40% concentration has Htde effect, but sulfur is oxidized by concentrated nitric acid in the presence of bromine with a strongly exothermic reaction (19). 

If bromine is used in equation 8, carbon tetrabromide [558-13-4] is formed. With a minor amount of iodine present, and in the absence of iron catalyst, carbon disulfide and chlorine react to form trichioromethanesulfenyl chloride (perchloromethyl mercaptan [594-42-3]), CCI3SCI, which can be reduced with staimous chloride or tin, and hydrochloric acid to form thiophosgene (thiocarbonyl chloride [463-71-8], CSCI2, an intermediate in the synthesis of many organic compounds (see Sulfurcompounds). 

A very efficient one-pot procedure for the production of 3-hydroxy-3-cephems (45) has been developed which gives the desired product in almost 80% overall yield from (43a) which is readily available from penicillin. TTie sequence of reactions is (1) mesylation to give (43b), (2) formation of enamine (43c), (3) bromination to afford (44) and (4) hydroly-sis/cyclization with hydrochloric acid in methanol to afford (45) which, in some cases, crystallizes directly from the reaction mixture (B-82MI51000). 

Kynar Liners Kynar (Pennwalt Chemicals Corp.) vinylidene fluoride liners are used for many chemicals, including bromine and 50 percent hydrochloric acid. 

From acetone in water and concentrated hydrochloric acid by addition of bromine. Hughes, Watson, and Yates, J. Chem. Soc. 1931, 3322. 

Bromine (128 g., 0.80 mole) is added dropwise to the well-stirred mixture over a period of 40 minutes (Note 4). After all the bromine has been added, the molten mixture is stirred at 80-85° on a steam bath for 1 hour, or until it solidifies if that happens first (Note 5). The complex is added in portions to a well-stirred mixture of 1.3 1. of cracked ice and 100 ml. of concentrated hydrochloric acid in a 2-1. beaker (Note 6). Part of the cold aqueous layer is added to the reaction flask to decompose whatever part of the reaction mixture remains there, and the resulting mixture is added to the beaker. The dark oil that settles out is extracted from the mixture with four 150-ml. portions of ether. The extracts are combined, washed consecutively with 100 ml. of water and 100 ml. of 5% aqueous sodium bicarbonate solution, dried with anhydrous sodium sulfate, and transferred to a short-necked distillation flask. The ether is removed by distillation at atmospheric pressure, and crude 3-bromo-acetophenone is stripped from a few grams of heavy dark residue by distillation at reduced pressure. The colorless distillate is carefully fractionated in a column 20 cm. long and 1.5 cm. in diameter that is filled with Carborundum or Heli-Pak filling. 4 hc combined middle fractions of constant refractive index are taken as 3-l)romoaccto])lu iu)nc weight, 94 -100 g. (70-75%) l).p. 75 76°/0.5 mm. tif 1.57,38 1.5742 m.]). 7 8° (Notes 7 and 8). 

The conversion of a-methyltropidine into tropidine methiodide was subsequently achieved in another way. By saturating a solution of the base in hydrochloric acid with hydrogen chloride, the elements of the latter were added on in the J -position and the product on treatment with sodium carbonate solution yielded methyl- -tropine. The latter was next brominated in positions 4 and 5, The dibromide, thus formed,... 

A solution of 16jS-methyl-l la,17a,21-trihydroxy-5j5-pregnane-3,20-dione 21-acetate (52), 45 g, in dioxane (297 ml) is cooled to 15° and treated over a 5 min period with a solution of bromine (34.2 g) in dioxane (594 ml) precooled to 18°. After 2 min a solution of sodium acetate (60 g) in water (600 ml) is added and the mixture poured into ice water (8 liters). The precipitate is filtered off, washed to neutrality with water, and dried to give the crude dibromide (53), 55.7 g mp 125-126° (dec.) [aJu 58°. A mixture of dibromide (53), 55.5 g, lithium bromide (27.8 g), lithium carbonate (27.8 g) and DMF (1.11 liters) is refluxed under rapid stirring for 6 hr. The mixture is concentrated under vacuum to about 250 ml, poured into ice water (8 liters) containing hydrochloric acid (250 ml), and extracted with methylene dichloride. The extracts are washed to neutrality with water and evaporated to dryness. The residue is dissolved in acetone, evaporated to dryness under reduced pressure, redissolved in acetone and crystallized by the additon of hexane. This gives the dienone (54) 24.4 g, mp 236-239°. 

The elements of bromine azide have been added to steroid olefins. The addition can be rationalized as proceeding through a positive bromonium ion under the ionic conditions of Hassner and Boerwinkle (bromine plus sodium azide and hydrochloric acid in nitromethane-dichloromethane) or Ponsold (A-bromosuccinimide or A-bromoacetamide in chloroform contain-... 

The acid (3 g) is refluxed with excess acetic anhydride for 45 min, and the excess anhydride evaporated in vacuo. The residue is dissolved in 100 ml. of chloroform and cooled in a bath of ice and hydrochloric acid. With stirring, a solution of 1.45 g of bromine (1 mole) in 50 ml of chloroform is added during 1 hr. Ozonized oxygen is passed through the cold solution until no more ozone is absorbed. The solvent is evaporated in vacuo below 30° and... 

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