Chlorobenzene-ammonia

The levels indicated by values 20, 232 and 339 kJ mol-1 correspond to A-protonated aniline produced by ion-molecule reactions (reagents depicted so in the insets) in the absence of collisional stabilization (a) lower ionized chlorobenzene-ammonia, (b) middle phenyldiazonium ion—ammonia and (c) upper phenyl cation-ammonia... 

Predict the products formed when each of the following isotopically substituted denvatives of chlorobenzene is treated with sodium amide in liquid ammonia Estimate as quantitatively as possible the composition of the product mixture The astensk ( ) in part (a) designates C and D in part (b) is... 

In a 500-ml. round-bottomed flask fitted with a reflux condenser are placed 16.2 g. (0.08 mole) of dry a-naphthylthiourea (Note 1) and 180 ml. of redistilled chlorobenzene. The flask is heated at the reflux temperature by means of an electric heating mantle. Evolution of ammonia begins almost at once, and all of the solid dissolves after 30-45 minutes. The solution is maintained at reflux for 8 hours (Note 2) and then evaporated on a steam bath at water-pump pressure to remove all of the chlorobenzene. The residue crystallizes on cooling and is extracted with four 30-ml. portions of boUing hexane (Note 3). Removal of solvent from the combined hexane extracts affords pale yellow crystals of naphthyl isothiocyanate, m.p. 58-59°. The yield is 12.7-13.0 g. (86-88%). Recrystallization from hexane (9 ml. of hexane for 1 g. of solute) gives colorless needles, melting point unchanged (Note 4). 

Evidence for symmetrical intermediates such as benzyne cannot be established by quantitative analysis of the reaction mixture unless a labelled starting substance is used. By applying labeling techniques, Roberts and his collaborators obtained results which indicated that benzyne (13) occurs as an intermediate in the amination of chlorobenzene with potassium amide in liquid ammonia. From chlorobenzene-1-C (12) about equal amounts of anUine-l-C (14) and aniline-2-C (15) were formed. More or less probable alternative... 

An alternative way to produce aniline is through ammonolysis of either chlorobenzene or phenol. The reaction of chlorobenzene with aqueous ammonia occurs over a copper salt catalyst at approximately 210°C and 65 atmospheres. The yield of aniline from this route is also about 96% ... 

It is important to learn if the same intermediate forms in several reactions, for if so its identity will very likely be manifest by the common features that can be observed. Here is an example cited by Bunnett.6 It was suspected that the reaction of chlorobenzene with potassium amide in liquid ammonia occurs by way of benzyne. Experiments were done with a I4C label (blackened) at the 1-position.14 The reaction gives equal amounts of aniline-1-14C and aniline-2-l4C,... 

Mobile phase 2-Propanol — chlorobenzene — /i-hecane — water — ammonia solution (25%) (52 + 34+ 20+10+ 5). 

The relative inertness of unactivated aromatic halides towards nucleophiles, under normal conditions, is in sharp contrast to their marked reactivity towards nucleophiles that are also very strong bases. Thus chlorobenzene is readily converted into aniline by reaction with eNH2 (NaNH2) in liquid ammonia at — 33° ... 

We know that nuclear halogens can be replaced by amine groups but with difficulty. Yet aniline has been manufactured from chlorobenzene by heating it with excess aqueous ammonia in presence of Cu20 at about 250° under pressure. 

Ammonolysis. Reactions involving ammonia. Ammonolysis of esters, acyl chlorides, and anhydrides give amides aniline is produced by ammonolysis of chlorobenzene. The reaction is analogous to hydrolysis, with ammonia substituted for water. 

Amarthol fast orange R base, see 3-Nitroaniline Amatin, see Hexachlorobenzene Ameisenatod, see Lindane Ameisenmittel merck, see Lindane American Cyanamid 3422, see Parathion American Cyanamid 4049, see Malathion Amerstat 274, see Ethylenediamine Amfol, see Ammonia Amidox, see 2,4-D Amine 2,4,5-T for rice, see 2,4,5-T Aminic acid, see Formic acid 2-Aminoacetylfluorene, see 2-Acetylaminofluorene 4-Aminoaniline, see / Phenylenediamine p-Aminoaniline, see / Phenylenediamine 2-Aminoanisole, see oAnisidine 4-Aminoanisole, see p-Anisidine oAminoanisole, see oAnisidine joAminoanisole, see p-Anisidine Aminobenzene, see Aniline p-Aminobiphenyl, see 4-Aminobiphenyl 1-Aminobutane, see Butylamine l-Amino-4-chloroaniline, see 4-Chloroaniline l-Amino-4-chlorobenzene, see 4-Chloroaniline 1-Amino-p-chlorobenzene, see 4-Chloroaniline 4-Aminochlorobenzene, see 4-Chloroaniline p-Aminochlorobenzene, see 4-Chloroaniline 4-Aminodiphenyl, see 4-Aminobiphenyl... 

From chlorobenzene Treatment of chlorobenzene with ammonia (NH3) at high temperature and high pressure in the presence of a catalyst yields aniline. 

The reactions of chlorobenzene and benzaldehyde with ammonia over metal Y zeolites have been studied by a pulse technique. For aniline formation from the reaction of chlorobenzene and ammonia, the transition metal forms of Y zeolites show good activity, but alkali and alkaline earth metal forms do not. For CuY, the main products are aniline and benzene. The order of catalytic activity of the metal ions isCu> Ni > Zn> Cr> Co > Cd > Mn > Mg, Ca, Na 0. This order has no relation to the order of electrostatic potential or ionic radius, but is closely related to the order of electronegativity or ammine complex formation constant of metal cations. For benzonitrile formation from benzaldehyde and ammonia, every cation form of Y zeolite shows high activity. 

In this work the reactions of ammonia with chlorobenzene and benz-aldehyde over a series of metal ion-exchanged zeolites were investigated by the microreactor method, and attempts were made to relate the catalytic activity of the zeolites to properties of metal cations. Ammonia was a reactant and a poison for acidic sites. 

To manufacture aniline from chlorobenzene and ammonia, cuprous oxide or diamino cuprous chloride has been used as the catalyst and the reaction is usually carried out in the liquid phase under pressure (7). There are few reports on the reaction in gas phase. Jones (8) found that CuX was active for aniline formation while ZnX led to the formation of dichlorobenzenes. The reaction of benzaldehyde with ammonia over zeolite has never been reported. 

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