Primary aromatic amines, reactions table

Primary aliphatic amines, 413 crystalline derivatives of, 424 reactions of, 420, 1072 table of, and derivatives of, 424 Primary aromatic amines, 539 crystalline derivatives of, 652 reactions and characterisation of, 648, 1073 ... 

In the reactions listed in Table 3, Michael addition of a primary aromatic amine to an a, (3-unsaturated aldehyde or ketone (prepared in situ) is followed by cyclization and oxidation of the intermediate dihydroquinoline to a quinoline (138 — 141). 

Kinetic measurements on reactions of an excess of phosgene with primary aromatic amines were carried out in toluene at -S, +5 and +25 C [436]. The results are summarized in Table 10.1, and the mechanism of the bimolecular nucleophilic substitution reaction is ... 

Pseudo-unimolecular rate constant (h ) at 91-6 t 90 0°. % For data on a number of primary aromatic amines see (cf. Table 5.19). Reaction too slow to permit calculation of accurate Arrhenius parameters. 

The activation energy of substitution of an unactivated aromatic halide (e.g., fiuorobenzene and 2-chloronaphthalene ) is over 30 kcal while that of activated compounds is 5-20 kcal. For the tabulated reactions (Tables II-VIII) with alkoxide and with primary, secondary, or tertiary amines, resonance activation (cf. 278 and 279) by ortho or para nitrogens is found to be greater than inductive activation (cf. 251). This relation is qualitatively demonstrated in... 

Reaction of a-isocyano-a, / -unsaturated sulfones with primary aliphatic amines affords 1,5-disubstituted imidazoles 59 (equation 56)48. The reaction of aromatic amines such as aniline is too slow to be of practical use. Results of the preparation of 59 are listed in Table 5. 

Primary, secondary and tertiary aliphatic amines are efficiently converted to nitro compounds in 80-90 % yield with dimethyldioxirane, a reagent prepared from the reaction of oxone (2KHSO5-KHSO4-K2SO4) with buffered acetone. Dimethyldioxirane (DMDO) has been used for the synthesis of 1,3,5,7-tetranitroadamantane (71) from the corresponding tetraamine as the tetrahydrochloride salt (70) and is an improvement over the initial synthesis using permanganate anion (Table 1.7). ° Oxone is able to directly convert some aromatic amines into nitro compounds. 

Morpholine (B) is the stronger base (pKb 5.79). It has a basicity comparable to that of secondary aliphatic amines. FVridine (A), a heterocyclic aromatic amine pl 8.75), is considerably less basic than aliphatic amines. Benzylamine (D), a primary aliphatic amine, is the stronger base (p/Cj, 3-4). o-Toluidine (C), an aromatic amine, is the weaker base (pKb 9-10). In the absence of Table 10.2, one can see that the electron pair on nitrogen in o-toluidine can participate in resonance with the benzene ring, while there are no resonance possibilities in benzylamine.This results in o-toluidine s electron pair being less available for reaction with an acid. 

The reactions were performed in an unmodified microwave oven. Prior to the microwave irradiation, 0.1 g of diacid chloride was ground with equimolar amount of an aromatic amine or diphenol and a small amount of a polar high boiling solvent (e.g., o-cresol, 0.05-0.45 ml) that acted as a primary microwave absorber. Under microwave irradiation, the polycondensation reactions proceeded rapidly (6-12 min) while compared with a conventional solution polymerization (reflux for 12 h in chloroform then for another 12 h in dimethylacetamide solutions [79]) to give polymers with higher inherent viscosities in the range of 0.36 to 1.93 dL/g (Table 5). 

The synthesis of pyrroles by the double trans addition to 1,3-diynes was first reported in 1961 [8]. A small amount (0.1 mol %) of copper(I) chloride promotes the addition of primary aliphatic and aromatic amines to 1,3-diynes at 150 to 180 °C (Table 20.1, entries 1 to 5). It was later found that the reaction of 1,3-diynes with 10 equiv of primary amines under solvent-free conditions in the presence of 10 mol % CuCl at 100 °C gave nearly quantitative yields of pyrroles (entries 6 to 8) [9]. 

Tertiary benzylic nitriles are useful synthetic intermediates, and have been used for the preparation of amidines, lactones, primary amines, pyridines, aldehydes, carboxylic acids, and esters. The general synthetic pathway to this class of compounds relies on the displacement of an activated benzylic alcohol or benzylic halide with a cyanide source followed by double alkylation under basic conditions. For instance, 2-(2-methoxyphenyl)-2-methylpropionitrile has been prepared by methylation of (2-methoxyphenyl)acetonitrile using sodium amide and iodomethane. In the course of the preparation of a drug candidate, the submitters discovered that the nucleophilic aromatic substitution of aryl fluorides with the anion of a secondary nitrile is an effective method for the preparation of these compounds. The reaction was studied using isobutyronitrile and 2-fluoroanisole. The submitters first showed that KHMDS was the superior base for the process when carried out in either THF or toluene (Table I). For example, they found that the preparation of 2-(2-methoxyphenyl)-2-methylpropionitrile could be accomplished h... 

Triazenes have been prepared by the treatment of resin-bound aromatic diazonium salts with secondary amines (Figure 3.27). Regeneration of the amine can be effected by mild acidolysis (Entry 1, Table 3.23). Triazenes have been shown to be stable towards bases such as TBAF, potassium hydroxide, or potassium tert-butoxide [454], and under the conditions of the Heck reaction [455]. Primary amines cannot be linked to supports as triazenes because treatment of triazenes such as R-HN-N=N-Ar-Pol with acid leads to the release of aliphatic diazonium salts into solution [373]. Triazenes derived from primary amines can, however, be used for the preparation of amides and ureas (see Section 3.3.4),... 

Thermoset polyurethanes are cross-linked polymers, which are produced by casting or reaction injection molding (RIM). For cast elastomers, TDI in combination with 3,3,-dichloro-4,4,-diphen5lmethanediamine (MOCA) are often used. In the RIM technology, aromatic diamine chain extenders, such as diethyltoluenediamine (DETDA), are used to produce poly(urethane ureas) (47), and replacement of the polyether polyols with amine-terminated polyols produces polyureas (48). The aromatic diamines are soluble in the polyol and provide fast reaction rates. In 1985, internal mold release agents based on zinc stearate compatibilized with primary amines were introduced to the RIM process to minimize mold preparation and scrap from parts tom at demold. Some physical properties of RIM systems are listed in Table 7. 

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