Mucic acid

After the 45 minutes heating, pour the contents of the flask into a large excess of cold water (about 300 ml.), in which the nitrobenzene, being heavier than water, sinks to the bottom. Stir the mixture vigorously in order to wash out as much acid as  [c.157]

The phenylarsonic acid should separate from the cold stirred solution within 10-20 minutes. If separation does not occur (due to the addition of too much acid), add a few drops of dilute aqueous sodium hydroxide and again bring the solution very carefully to the desired pH.  [c.313]

Obtain a 250 ml. round-bottomed fiask and attach an efficient refiux condenser to it by means of a clean rubber stopper. (The rubber stopper is cleaned by warming with dilute alkali, and then thoroughly washing with distilled water.) Place the sample of ester in a weighing bottle fitted with a cork carrying a small dropper pipette (compare Fig. //, 27, 1) transfer about 1 g. of the ester, accurately weighed, to the flask. Then introduce 50 ml. of standard 0 -5N alcoholic potassium hydroxide solution by means of a pipette into the flask, add a few chips of broken glass, attach the reflux condenser, and heat the flask gently on a water bath until hydrolysis is complete (1-5-2 hours). When cold, pour about 50 ml. of distilled water through the condenser, add 2-3 drops of phenol-phthalein indicator, and titrate the excess of alkaU with standard 0 5N or 0 25N hydrochloric or sulphuric acid. The end point should be a faint pink. If too much acid is accidentally added, back titrate the excess of  [c.392]

Lactose (hydrated). Lactose (anhydrous) 2031 223 + 52-5 200 — Octa-acetate, a- 152, P- 90 mucic acid, 213  [c.457]

A. Maleic acid. Assemble the apparatus shown in Fig. Ill, 28, 1. Place 45 g. of dry mahc acid in the 200-250 ml. distilling flask and cautiously add 63 g. (57 ml.) of pure acetyl chloride. Warm the flask gently on a water bath to start the reaction, which then proceeds exothermically. Hydrogen chloride is evolved and the malic acid passes into solution. When the evolution of gas subsides, heat the flask on a water bath for 1-2 hours. Rearrange the apparatus and distil. A fraction of low boiling point passes over first and the temperature rises rapidly to 190° at this point run out the water from the condenser. Continue the distillation and collect the maleic anhydride at 195-200°. Recrystallise the crude maleic anhydride from chloroform (compare Section 111,93) 22 g. of pure maleic anhydride, m.p. 54°, are obtained.  [c.462]

JV-Methylpyrrole. Prepare the methylamine salt of mucic acid by adding slowly and with vigorous stirring 260 ml. of lOA aqueous methyl-amine to 210 g. of mucic acid if difficulty is experienced in stirring the mixture, add up to 100 ml. of water. Complete the preparation following the experimental conditions given above for Pyrrole. The yield of iV-methylpyrrole, b.p. 110-113°, is 32 g. The compound is very hygroscopic and darkens on standing keep it in a tightly-stoppered, brown bottle.  [c.838]

Galactose and also carbohydrates which yield galactose upon hydrolysis (e.g., lactose) are oxidised to the sparingly soluble mucic acid (compare Section II 1,139).  [c.1070]

Oxidation of galactose (or a galactose-containing sugar) to mucic acid. Dissolve 1 g. of galactose or lactose in a mixture of 10 ml. of water and 5 ml. of concentrated nitric acid contained in a small evaporating dish, and evaporate the solution to dryness on a water bath. Stir the cold residue with 10 ml. of cold water, filter off the mucic acid, wash it with cold water, dry and determine the m.p. (212-213° with decomposition).  [c.1070]

Carbocations, Magic Acid, and Superacid Chemistry  [c.84]

After the 45 minutes heating, pour the contents of the flask into a large excess of cold water (about 300 ml.), in which the nitrobenzene, being heavier than water, sinks to the bottom. Stir the mixture vigorously in order to wash out as much acid as  [c.157]

The phenylarsonic acid should separate from the cold stirred solution within 10-20 minutes. If separation does not occur (due to the addition of too much acid), add a few drops of dilute aqueous sodium hydroxide and again bring the solution very carefully to the desired pH.  [c.313]

Remove 25 ml. by means of a pipette, add a few drops of phenolphthalein the colour is pink. Now add very cautiously, drop by drop, dilute acetic acid (say M/too) until the pink colour has us/ not disappeared. It is important not to add too much acid, otherwise the casein will be precipitated. Now add 5 ml. of neutralised formalin (see p. 464) and then titrate with Af/io NaOH solution. Note the amount required.  [c.518]

M. tuberculosis M-type ferrites Mucic acid  [c.650]

Physical Properties. Mahc acid crystallines from aqueous solutions as white, translucent, anhydrous crystal. The S(—) isomer melts at 100-103°C (1) and the R(+) isomer at 98-99°C (2). On heating, D,L-mahc acid decomposes at ca 180°C by forming fumaric acid and maleic anhydride. Under normal conditions, malic acid is stable under conditions of high humidity, it is hygroscopic.  [c.520]

Mahc acid is a relatively strong acid. Its dissociation constants are given in Table 1. The pH of a 0.001% aqueous solution is 3.80, that of 0.1% solution is 2.80, and that of a 1.0% solution is 2.34. Many of its physical properties are similar to those of citric acid (qv). Solubihty characteristics are shown in Figure 1 and Table 1, densities of aqueous solutions are hsted in Table 2, and pH values vs concentration are shown in Figure 2.  [c.520]

As a dibasic acid, malic acid forms the usual salts, esters, amides, and acyl chlorides. Monoesters can be prepared easily by refluxing malic acid, an alcohol, and boron trifluoride as a catalyst (9). With polyhydric alcohols and polycarboxyUc aromatic acids, malic acid yields alkyd polyester resins (10) (see Alcohols, polyhydric Alkyd resins). Complete esterification results from the reaction of the diester of maUc acid with an acid chloride, eg, acetyl or stearoyl chloride (11).  [c.521]

Occurrence. S(—)-Mahc acid occurs widely in biological systems. It is the predominant acid in many fmits (Table 4). However, malic acid occurs in relatively low concentrations, thus making its isolation from natural sources expensive and impractical.  [c.522]

Antimonypentafluoride, SbFj, m.p. 7 C, b.p. 150 C is an associated liquid (Sb plus F2 or SbClj plus HF). Forms many complexes and complex ions including [ShF ]", [Sb2Fu]" and is a very powerful fluoride ion acceptor. Greatly enhances the dissociation of, e.g. HF and HSO3F by forming anionic species (magic acid, super acid). Used as a fluorinating agent (sometimes in the form of its graphite intercalation compound).  [c.39]

Remove 25 ml. by means of a pipette, add a few drops of phenolphthalein the colour is pink. Now add very cautiously, drop by drop, dilute acetic acid (say Mjioo) until the pink colour has just not disappeared. It is important not to add too much acid, otherwise the casein will be precipitated. Now add 5 ml. of neutralised formalin (see p. 464) and then titrate with Mj 10 NaOH solution. Note the amount required.  [c.518]

Vigorous oxidation of a monosaccharide (e.g., with dUute nitric acid) produces carboxyl groups at both ends of the chain. Thus galactose gives the sparingly soluble mucic acid glucose affords the soluble saccharic acid, which is best isolated as the sparingly soluble acid potassium salt.  [c.452]

COoH Saccharic acid 1 CHjOH Galactose 1 COjH Mucic acid  [c.452]

Dissolve 10 g. of lactose (1) in 100 ml. of nitric acid, sp. gr. 115, in an evaporating dish and evaporate in a fume cupboard until the volume has been reduced to about 20 ml. The mixture becomes thick and pasty owing to the separation of mucic acid. When cold, dilute with 30 ml. of water, filter at the pump and set the filtrate A) aside. Wash the crude acid with cold water. Purify the mucic acid by dissolving it in the minimum volume of dilute sodium hydroxide solution and reprecipitating with dilute hydrochloric acid do not allow the temperature to rise above 25°. Dry the purified acid (about 5 g.) and determine the m.p. Mucic acid melts with decomposition at 212-213°.  [c.453]

Place 50 g. (35 ml.) of concentrated nitric acid in a 500 ml. round-bottomed flask, and add, in portions with shaking, 74 g. (40 ml.) of concentrated sulphuric acid. Keep the mixture cool during the addition by immersing the flask in cold water. Place a thermometer (110° range) in the acid mixture. Introduce 26 g. (30 ml.) of benzene in portions of 2-3 ml. shake the flask well, to ensure thorough mixing, after each addition of the benzene. Do not allow the temperature of the mixture to rise above 55° immerse the flask, if necessary, in cold water or in ice water. When all the benzene has been added, fit a reflux condenser to the flask and heat it in a water bath maintained at 60° (but not appreciably higher) for 40-45 minutes remove the flask from time to time from the bath and shake it vigorously to ensure good mixing of the immiscible layers. Pour the contents of the flask into about 500 ml. of cold water in a beaker, stir the mixture well in order to wash out as much acid as possible from the nitrobenzene, and allow to stand. When the nitrobenzene has settled to the bottom, pour off the acid hquor as completely as possible, and transfer the residual liquid to a separatory funnel. Rim off the lower layer of nitrobenzene and reject the upper aqueous layer return the nitrobenzene to the separatory funnel and shake it vigorously with about 50 ml. of water. Separate the nitrobenzene as completely as possible and run it into a small conical flask containing about 5 g. of anhydrous calcium chloride. If the nitrobenzene does not become clear on shaking because of the presence of emulsified water, warm the mixture, with shaking, for a short period on a water bath the cloudi ness will soon disappear. Filter the cold product through a small fluted filter paper into a small (50 or 100 ml.) distilling flask attached to an air condenser (Fig. II, 13, 2). Heat the flask on an asbestos-centred wire gauze or preferably in an air bath (Fig. II, 5, 3) and collect the fraction which boils at 206-211°. Do not distil quite to dryness nor allow the  [c.525]

Prepare a solution of 30 g. of sodium hydroxide in 120 ml. of water in a 350 ml. conical flask and cool to 0° or below in a bath of ice and salt. Add 26 -2 g. (8 -4 ml.) of bromine in one portion and shake (or stir) until aU the bromine has reacted. The temperature will rise somewhat cool again to 0° or below. Meanwhile, prepare a solution of 22 g. of sodium hydroxide in 80 ml. of water. Add 24 g. of finely-powdered phthalimide (Section IV,169) in one portion to the cold sodium hypo-bromite solution stir vigorously while swirling the contents of the flask and add the prepared sodium hydroxide solution rapidly. The solid will dissolve and the temperature will rise to about 70°, Warm the mixture to 80° for about 2 minutes. Filter, if necessary. Cool in ice and add concentrated hydrochloric acid slowly and with stirring until the solution is jvM neutral (about 60 ml. are required), [It is recommended that a little of the alkaline solution be set aside in case too much acid is added.] Precipitate the anthranilic acid completely by the gradual addition of glacial acetic acid (20-25 ml. are required) it is advisable to transfer the mixture to a 1 litre beaker as some foaming occurs. Filter oflF the acid at the pump and wash with a little cold water. Recrystallise from hot water with the addition of a little decolourising carbon collect the acid on a Buchner funnel and dry at 100°. The yield of pure anthranilic acid, m.p. 145°, is 14 g.  [c.773]

Pyrolysis of the methylamine salt (produced by neutralising mucic acid with aqueous methylamlne) in the presence of glycerol yields JV-methylpyrrole  [c.837]

Place 210 g. of mucic acid (Section 111,138) and 300 ml. of concentrated ammonia solution (sp. gr. 0 -88) in a large evaporating dish and rapidly stir the mixture to a smooth paste (FUME CUPBOARD ). Evaporate the paste to dryness on a water bath, powder the resulting ammonium mucate and mix it with 120 ml. of glycerol in a 2 litre round bottomed Pyrex flask. Allow to stand overnight. Arrange for distillation with a filter or distilling flask as receiver connect the latter to a gas trap (Fig. II, 8, 1, c). Distil the mixture carefully with a free flame. Apply the heat initially to one side of the flask so that only a portion of the mass is heated to the reaction temperature considerable frothing ensues and this must be controlled by removing the flame from below the flask and heating the upper portion of the vessel above the surface of the boiling mixture. Extend the heating as rapidly as possible throughout the mass with due regard to the control of the foaming. Continue the distillation until a sample of the distillate no longer gives oily drops when treated with solid potassium hydroxide the total volume of distillate is 300-350 ml. Redistil the distillate until no further oil separates in the liquid which passes over. Separate the oil, dry it rapidly with potassium hydroxide pellets, and stil. Collect the pyrrole (a colourless liquid) at 127-131° the yield is 25 g. The pyrrole should be stored in a sealed vessel it darkens upon exposure to light.  [c.838]

TaF, and NbF and other strong Lewis acids such as B(03SCF3)3 were also successfully introduced. The name magic acid for the FS03F1-SbF system was given by Joe Lukas, a German postdoctoral fellow working with me in Cleveland in the 1960s, who after a laboratory Christmas party put remainders of a candle into the acid. The candle dissolved, and the resulting solution gave a clear NMR spectrum of the tert-butyl cation. This observation understandably evoked much interest, and the acid used was named magic. The name stuck in our laboratory. I think it was Ned Arnett who learned about it during one of his visits and subsequently introduced the name into the literature, where it became quite generally used. I helped a former graduate student of mine, Jim Svoboda, start a small company (Cationics) to make some of our superacidic systems and reagents commercially available, and he obtained trade name protection for Magic Acid. It has been marketed as such since that time.  [c.96]

Starting in the late 1950s, I was fortunate to have found superacidic antimony pentafluoride, magic acid, and other related systems and to be able to explore their remarkable chemistry. The strength of some of these acids can be up to trillions of times stronger than that of concentrated sulfuric acid. Such large numbers have little meaning in our everyday life, and it is even difficult to comprehend their magnitude. As a comparison, the U.S. national debt is about 6 trillion dollars (6 X 10 ). Superacids are indeed extremely strong, considering that they are obtained in the condensed state, where the naked proton cannot exist. In the gas phase—for example, in a mass spectrometer at high vacuum—in contrast, the proton can be unencumbered, i.e., naked. This could be estimated to add an additional 30-35 powers of tens to the imagined (or unimaginable) Ho acidity. In the condensed state, a proton lacking any electron will always attach itself to any electron donor. It is with this caveat that we use H to denote the proton when discussing its role in condensed-state chemistry.  [c.100]

The high acidity of superacids makes them extremely effective pro-tonating agents and catalysts. They also can activate a wide variety of extremely weakly basic compounds (nucleophiles) that previously could not be considered reactive in any practical way. Superacids such as fluoroantimonic or magic acid are capable of protonating not only TT-donor systems (aromatics, olefins, and acetylenes) but also what are called (T-donors, such as saturated hydrocarbons, including methane (CH4), the simplest parent saturated hydrocarbon.  [c.100]

Maghemite [12134-66-6] Magic acid Magic Acid MagicAcid [33843-68-4] Magic Carpet system Magma  [c.584]

Mucic acid [526-99-8] Mucoadhesives Muconic acid [505-70-4] Mucopolysaccharidoses Mucor circinelloides Mucor spp.  [c.650]

L. van Zelst, ia S. L. Hyatt, ed.. The Greek Uase, Hudsoa-Mohawk Associatioa of CoUeges and Universities, Latham, N.Y., 1981, pp. 119—134.  [c.431]

Malic Acid. Make acid [6915-15-7] C H O, similar to citric acid in acidifying character and flavor, does not exhibit the initial burst of tartness that citric acid does. Make acid is mostly used in fmit-flavored carbonated beverages, but its high solubikty and low melting point make it ideal for hard candy appkeations. Make acid is synthesized by hydrating maleic acid and fumaric acid in the presence of a catalyst, then separating malic from the mixture by equikbrium techniques (11).  [c.436]

In the early 1960s acid systems were prepared comprising a pentafluoride of group V elements, particularly SbF and a strong Brninsted acid such as HF, FSO H, CF SO H, etc (218). Magic Acid [33843-68-4] (HSO F—SbF ) is one of the strongest members of the system fliioroantimonic acid [16950-06-4] HF—SbF, even surpasses Magic Acid in its acidity. The acidity of HF or HSO F is increased sharply by a dding SbF (219,220). These very highly acidic systems ate being utilized in transformations such as isomerization of straight-chain alkanes (221), Alkane—alkene alkylations (222), and the like (223). CF SO H—SbF and CF SO H—B(OTf)2 have been shown to be highly effective catalysts for Friedel-Crafts alkylation and isomerization reactions (224).  [c.565]

Reactions. Mahc acid undergoes many of the characteristic reactions of dibasic acids, monohydric alcohols, and a-hydroxycarboxyUc acids. When heated to 170—180°C, it decomposes to fumaric acid and maleic anhydride which sublimes on further heating (see Maleic anhydride, maleic acid, AND FUMARIC acid). MaUc acid forms two types of condensation products linear malomalic acids and the cycHc dilactone or maUde it does not form an anhydride.  [c.521]

In addition to its presence in fmits, S(—)-malic acid has been found in cultures of a variety of microorganisms including the aspergiUi, yeasts, species of Sekrotinia, and Penicillium brevicompactum. Yields of levorotatory malic acid as high as 74% of theoretical have been reported. Iron, manganese, chromium, or aluminum ions reportedly enhance malic acid production. S(—)-Mahc acid is involved in two respiratory metaboHc cycles the Krebs tricarboxylic acid  [c.522]

See pages that mention the term Mucic acid : [c.266]    [c.452]    [c.453]    [c.95]    [c.98]    [c.99]    [c.99]    [c.192]    [c.520]    [c.522]   
See chapters in:

Textbook on organic chemistry  -> Mucic acid

Textbook on organic chemistry (1974) -- [ c.452 , c.1070 ]