Acid Hydrochloric Anhydride

The alkylidene dimethone (dimedone) (I) upon boiling with glacial acetic acid, acetic anhydride, hydrochloric acid and other reagents frequently loses water and passes into a substituted octahydroxanthene or the anhydride (II), which often serves as another derivative. The derivatives (I) are soluble in dilute alkali and the resulting solutions give colourations with ferric chloride solution on the other hand, the anhydrides (II) are insoluble in dilute alkali and hence can easily be distinguished from the alkylidene dimedones (I). 

Place a mixture of 17 -5 g. p-chlorobenzoyl chloride (1) and 50 ml. of dry pyridine (Section 11,47,22) in a loosely-stoppered 250 ml. flask and warm on a steam hath for 5 minutes. Pour the reaction mixture upon 100 g. of crushed ice and 50 ml. of concentrated hydrochloric acid. The anhydride separates out at once. When the ice has melted sufficiently, filter the mixture by suction. Wash the sohd with 15 ml. of methanol and then with 15 ml. of dry benzene. The yield of crude p-chlorobenzoic anhydride is 14 5 g. Recrystalhse from 250 ml. of dry benzene 13 g. of the pure anhydride, m.p. 192-193°, are obtained. 

Phenyl isothiocyanate has been prepared from thiocarbanilide by the action of phosphorus pentoxide, hydrochloric acid, iodine, phosphoric acid, acetic anhydride, and nitrous acid. It has also been prepared from ammonium phenyl dithiocarbamate by the action of ethyl chlorocarbonate, copper sulfate lead carbonate, lead nitrate, ferrous sulfate,and zinc sulfate. ... 

Semicarbazones are prepared in high yields from A " -3-ketones. However, regeneration of the parent dienone is usually difficult and inefficient and very low yields are usually obtained on hydrolysis by nitrous acid, hydrochloric acid or acetic anhydride-pyridine. " In some examples higher yields have been obtained with aqueous acetic acid. ... 

Agrawal and co-workers" " also conducted extensive studies into the synthesis, characterization and thermal and explosive behaviour of (113) (K-56, TNABN). 2,5,7,9-Tetraazabi-cyclo[4.3.0]nonane-8-one (112) was synthesized from the direct reaction of ethylenediamine with glyoxal, followed by reaction of the resulting cyclic imine with urea in concentrated hydrochloric acid nitration of (112) was achieved in 51 % yield with a mixture of nitric acid-acetic anhydride. Agrawal showed that K-56/TNABN is significantly more resistant to hydrolytic destruction than TNGU. 

Boyer and co-workers" also reported the synthesis of the guanidine tricycle (122), prepared as the tetrahydrochloride salt from the condensation of two equivalents of guanidine with 1,4-diformyl-2,3,5,6-tetrahydroxypiperazine in concentrated hydrochloric acid. Treatment of the tricycle (122) with absolute nitric acid yields thebis-nitrimine (123), whereas the same reaction with nitric acid-acetic anhydride yields HHTDD (117). 

Formaldehyde, Methylnitramine, Methylene chloride, Magenesium sulfate. Sulfuric acid. Chloroform, Hexane Nitric acid. Diethanolamine, Ethanol, Ether, Acetone Potassium permanganate, 3-Amino-l,2,4-triazole, Sodium hydroxide. Sodium bisulfite. Hydrochloric acid. Nitric acid, Acetic anhydride. Acetone... 

Potassium permanganate, 3-Amino-l,2,4,triazole, Sodium hydroxide. Sodium bisulfite. Hydrochloric acid, Nitric acid. Acetic anhydride. Acetone... 

Reaction XCVII. Hydrolysis of Amides, Acid Chlorides and Acid Anhydrides. (A., 188, 73 B., 26, R 773 28, R., 917, 32, 1118.)—All these compounds on hydrolysis yield acids. The anhydrides are hydrolysed by treatment with water or dilute alkali, the acid chlorides are usually very rapidly hydrolysed by water, but in the aromatic series 10% caustic alkali is sometimes necessary. The amides are boiled with caustic alkali solution (10%) or with cone, hydrochloric or sulphuric acid. They are, especially the substituted aromatic amides, very resistant to the action of acids, so that the former method is the best. Another method is to dissolve the amide in cone, sulphuric acid, and add sodium nitrite in the cold, afterwards gently warming. Sometimes dilute sulphuric acid and addition of the nitrite in the warm gives better results. 

An extensive study, summarized in Table VII, was carried out which established the effect of hydrochloric acid-succinic anhydride as combined activators on properties of boards made using maleic anhydride as the crosslinking agent. Data in Table VII is presented in two parts. In Fart A experiments are summarized in which either one or two of the three additives tab re used in the formulations in Part B all three additives were used. 

Triethylamine Hydrochloric acid Acetic anhydride Diphenylacetylene... 

Acetic acid, hydrochloric acid, and acetic anhydride were obtained from Fisher Scientific. 

A one-step allylic rearrangement-of a 17/3-hydroxy-17a-vinyl steroid (21) in acidified acetic acid-acetic anhydride gave the 21-acetoxypregn-17(20)-ene (22) in 60—65% yield,59 improving upon an earlier two-step sequence via the 21-chloro-derivative. 17/8-Hydroxy-17a-vinyl steroids (21) are converted into ( )-pregn-17(20)-enes (24) by reaction first with thiourea and hydrochloric acid to give the rearranged thiuronium salt (23), followed by reduction with sodium-ammonia.60... 

If R is aromatic with electron-withdrawing substituents, the acid is the major prodnct. Becanse the anhydride is thought to be in eqnilibrium with the acid in solution, the separation conditions can determine whether the acid or anhydride is obtained. Becanse many dihaloarsines dissolve in water withont appreciable hydrolysis, the addition of base is required to form the acid salt. Reduction of an arsonic acid, RAsO(OH)2, in hydrochloric acid with SO2 and as a catalyst gives the anhydride (eqnation 127). The anhydride is also produced during the oxidation of cyclopolyarsines and primary arsines in the absence of water (equation 128). 

Explodes on contact with acetic acid, acetic anhydride, ammonium nitrate, dimethylformamide, formaldehyde, concentrated hydrochloric acid, potassium chloride + sulfuric acid, sulfuric acid + water. Forms sensitive explosive mixtures with aluminum powder + ammonium nitrate + glyceryl nitrate + nitrocellulose, ammonium perchlorate, arsenic, phosphorus, sulfur, slag wool, titanium. 

At this point aniline can be isolated. You could reduce the solubility of aniline by dissolving in the steam distillate 0.2 g of sodium chloride per milliliter, extract the aniline with 2-3 portions of dichloromethane, dry the extract, distill the dichloromethane (bp 4rC), and then distill the aniline (bp 184°C). Or the aniline can be converted directly to acetanilide. The procedure calls for pure aniline, but note that the first step is to dissolve the aniline in water and hydrochloric acid. Your steam distillate is a mixture of aniline and water, both of which have been distilled. Are they not both water-white and presumably pure Hence, an attractive procedure would be to assume that the steam distillate contains the theoretical amount of aniline and to add to it, in turn, appropriate amounts of hydrochloric acid, acetic anhydride, and sodium acetate, calculated from the quantities given in Experiment 2. 

If acetyl chloride (2 mL) is substituted for the hydrochloric acid-acetic anhydride mixture in the procedure, the Z-isomer is the sole product. 

When heated at 150° C. phenylmercuric acetate gives carbon, benzene, mercury, oxygen, and acetic anhydride. Dry distillation yields mercury, diphenyl oxide, and acetic anhydride. Distillation with sulphur gives mercury, benzene, acetic acid, acetic anhydride, and diphenyl sulphide. Boiling with dilute sulphuric or hydrochloric acid produces benzene, acetic acid, and a mercuric salt. The acetate is reduced by nascent hydrogen to benzene, mercury, and acetic acid. 

The following compounds when heated with hydrochloric acid yield mercuric chloride and an organic acid The anhydride of o-hydroxy-mercuri benzoic acid and the anhydride of a-hydroxy mercuri- -hydroxy-j3-phenyipropionic acid, whilst o-chloromercuri benzoic methyl ester is decomposed by halogen acids, and cold dilute hydrochloric acid eliminates the acetoxymercuri group attached to the nitrogen in N-isodiacetoxymercuri anthranilic methyl ester. 

Manufacture of many important amino intermediates used for dyes and other purposes is usually by conversion or replacement of a substituent. For example, as already mentioned, in substituted nitro compounds, the nitro groups may be reduced with iron/hydrochloric acid, hydrogen and catalyst, or zinc in aqueous alkali. Partial reductions can be brought about with sodium sulfide. Amino groups may be introduced by replacing halogens in the aromatic ring. Another approach to amination is by attack on a substituted aromatic compound with ammonia or amines. Thus, for example, direct amination of p-chloronitrobenzene (15a) in the presence of a copper catalyst affords p-nitroaniline (15b) in almost quantitative yield l,4-dichloro-2-nitrobenzene (16) is converted in a similar way to 4-chloro-2-nitroaniline (17). Reactions of ammonia with carboxylic acids or anhydrides are carried out on an industrial scale. 

For bringing about the first reaction the following-named substances may be used as condensation agents hydrochloric acid, acetic anhydride, as well as primary and secondary amines (ethyl amine, diethyl amine, piperidine, and others). For the second reaction the bases mentioned may be used. A small quantity of one of these may produce la rge quantities of the condensation product this is a case of a so-called continuous reaction. It is probable that the amine reacts first with the aldehyde, water being eliminated 1... 

I,2,3-Benzotriazin-4-ones are useful reagents in peptide synthesis and may be synthesized from the anthranilic acid by successive reaction with thionyl chloride (which forms an unstable sulphinamide anhydride), O-(trimethylsilyl)hydroxylamine and a nitrous acid-hydrochloric acid mixture at low temperature. 

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