C-acids

Required N-Vhtny znxhx2J i c acid, 4 g. sulphuric acid, 10 ml. 

C) Acids. Employ oxidation to acids (see 6 above) only if C4H5CHO or a substituted derivative is suspected. Aliphatic aci may be too soluble for ready isolation. 

Coinpou nd Position of Nil ration Temperature TO l ow Acidity ( furclntion Slope Coenicient Species Rcnclirg High Temperature ("C) Acidity Slope Species Reacting... 

MALEIC ANHYDRIDE,lvLALEIC ACID ANDFUlvLAR[C ACID] (Vol 15)... 

The product of this reaction can be removed as an azeotrope (84.1% amide, 15.9% acetic acid) which boils at 170.8—170.9°C. Acid present in the azeotrope can be removed by the addition of soHd caustic soda [1310-73-2] followed by distillation (2). The reaction can also take place in a solution having a DMAC-acetic acid ratio higher than the azeotropic composition, so that an azeotrope does not form. For this purpose, dimethylamine is added in excess of the stoichiometric proportion (3). If a substantial excess of dimethylamine reacts with acetic acid under conditions of elevated temperature and pressure, a reduced amount of azeotrope is formed. Optimum temperatures are between 250—325°C, and pressures in excess of 6200 kPa (900 psi) are requited (4). DMAC can also be made by the reaction of acetic anhydride [108-24-7] and dimethylamine ... 

Fig. 9. Schematic of KNO2 from NH2 and KCl A, KCl—HNO2 reactor B, NOCl oxidizer C, acid eliminator D, gas stripper E, water stripper F, H2O—HNO2 fractionator G, evaporator—crystallizer H, centrifuge I, NO—NO2 absorber , NH2 burner K, CI2 fractionator and L, NO2 fractionator.

L-tyrosine D-tyrosine DL-tyrosine Heterogclic proline [60-18 ] [556-02-5] [556-03-6] [7005-20-1 ] Pro 2-pyrrobdine-carboxyb c acid N COOH 115.13... 

The acidic double salt of ammonium acetate and acetic acid [25007-86-7], CH COONH CH COOH, is made by dissolving the neutral salt in hot acetic acid or by distilling the neutral salt. During distillation the acid salt is formed as a heavy oil that solidifies on cooling. It crystallizes as long, dehquescent needles that melt at 66 °C. Acid ammonium acetate is readily soluble in both water and alcohol. 

The moisture content of cmde sulfur is determined by the differential weight of a known sample before and after drying at about 110°C. Acid content is determined by volumetric titration with a standard base. Nonvolatile impurities or ash are determined by burning the sulfur from a known sample and igniting the residue to remove the residual carbon and other volatiles. 

Castor Wax. Castor wax [8001-78-3] is catalyticahy hydrogenated castor bean oil. The wax has a melting point of 86°C, acid number of 2, saponification number of 179, and an iodine number of 4. Castor wax is used primarily in the formulation of cosmetics. Derivatives of castor wax are used as surfactants and plastics additives. 

Federal name O Glycero 1 CH3O H C3H3O H Petroleu m jelly Toluen e Steari c acid Olei c acid Mineral oil Ethy 1 ethe r Aceton e Butyl acetate... 

Koch acid [117 2-0] 8-nitronaphthalene- 1,3,6-trisulfoni c acid iron... 

Maleic hydrazide (149), produced on a large scale as a herbicide, can be obtained, according to a patent, from a simple diaziridine, which on an industrial scale could be less expensive than hydrazine hydrate. In the proposed manufacture of diamide (150) from a diaziridine and urea it must be taken into account that the reaction of urea is preceded by solvolytic hydrazine formation, which probably proceeds under the reported conditions (several hours, 70-80 °C, acidic media) (79AHC(24)63). 

Methoxy 6( 2 Chlorobenzoyl)-ben2o(c acid (2).2 3-Metboxy-2(3-cblorobenzoyl)-benzolc acid 1 (1.0 g, 3.4 mmoQ was heated In cone. H2S04 (6 mL) for 1 h at 6S°C. The cooled reaction mixture was poured into ice and neutralized. The cyclized product was filtered off (0 2 g) and the filtrate was acidHIed to give 2, rrp 205°C. 

Amines can also be protected by this reagent cleavage must be carried c acidic media to avoid amine oxidation. The byproduct naphthoquinone can 1 moved by extraction with basic hydrosulfite. Ceric ammonium nitrate also s as an oxidant for deprotection, but the yields are much lower. 

Ammonium chloroplatinate often can be used to advantage in place of chloroplatim c acid in the preparation of Adams catalyst. A mixture of 3 g. of ammonium chloroplatinate and 30 g. of sodium nitrate in a casserole or Pyrex beaker is heated gently at first until the rapid evolution of gas slackens and then more strongly until a temperature of 500° is reached. This operation requires about fifteen minutes and there is no spattering. The temperature is held at 500-520° for one-half hour and the mixture is then allowed to cool. The platinum oxide catalyst, collected in the usual way by extracting the soluble salts with water, weighs 1.5 g. and it is comparable in appearance and in activity to the material prepared from chloroplatinic acid. 

Metal oxides. Zinc oxide is the most effective metal oxide. The zinc oxide should have a low lead content. Zinc oxide has three main functions (a) promote cure (b) improves ageing, heat and weathering resistance (c) acid acceptor. In general, 2-5 phr zinc oxide is added in latex formulations. 

Propcrtici>. ] c acid foims microscopic crystals of a charac-teiistlc shape. It is insoluble in water, but dissolves in the presence of many organic substances. On dry distillation it yields ammonia, cyanuiic acid, and urea. 

Hydrobromic Acid.—The weak solution of hydrobrom i c acid which collects in the beaker in the course of the above r -... 

FIGURE 4.3 The 20 amino acids diat are the building blocks of most proteins can be classified as (a) nonpolar (hydrophobic), (b) polar, nentral, (c) acidic, or (d) basic. 

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