Benzoic acid, reaction with ammonia

Curtin et. al. W exposed benzoic acid crystals to ammonia gas and generated ammonium benzoate. As shown In Figure 7, the (101) faces of the crystals become opaque while the (001) faces remain clear. The resistance of molecules at the (001) faces to reaction with ammonia Is explainable by the relatively unexposed carboxyl groups within this region. 

The reactions with ammonia can also be extended to benzoic acid anhydrides(VIII) in this case the products are a mixture of the ammonium salt (VI) and the benzamide (IX) [6, 9]. Arguments similar to those above can be used to explain the observed reaction anisotropy. Of particular interest, however, is the case of p-bromobenzoic anhydride ((VIII), X=Br). p-Bromobenzoic anhydride crystallizes in the space group... 

Snia Viscosa. Catalytic air oxidation of toluene gives benzoic acid (qv) in ca 90% yield. The benzoic acid is hydrogenated over a palladium catalyst to cyclohexanecarboxyhc acid [98-89-5]. This is converted directiy to cmde caprolactam by nitrosation with nitrosylsulfuric acid, which is produced by conventional absorption of NO in oleum. Normally, the reaction mass is neutralized with ammonia to form 4 kg ammonium sulfate per kilogram of caprolactam (16). In a no-sulfate version of the process, the reaction mass is diluted with water and is extracted with an alkylphenol solvent. The aqueous phase is decomposed by thermal means for recovery of sulfur dioxide, which is recycled (17). The basic process chemistry is as follows ... 

The reduction of a benzenoid ring, except in benzoic acid derivatives, occurs only in the presence of a proton donor having a pKa of 19 or less (pKa of ammonia is about 33). With the exception of the vinyl group, the other functional groups listed above do not require a proton donor of this acidity in order to be reduced, although the course of reduction may then be complex, e.g. as with esters. " Consequently, a variety of functional groups should be capable of selective reduction in the presence of a benzenoid ring if the reaction medium does not contain an acid of pKa <19. A few examples of such selective reductions have been reported in the steroid literature. 

A substituted benzoic acid serves as precursor for the nontricyclic antidepressant bipena-mol (175). Selective. saponification of ester 171 afford.s the half-acid 172. Reaction of the acid chloride derived from this intermediate (173) with ammonia gives the amide 174. Reduction of the last by means of lithium aluminum hydride gives bipenamol (175) [44]. 

Ten grams (0.082 mole) of benzoic acid is added to 100 ml. of anhydrous ethanol in a 2-1. three-necked flask equipped with a mechanical stirrer and with loose cotton plugs in the side necks. After the benzoic acid has dissolved, 600 ml. of liquid ammonia (Note 1) is added to the stirred solution. Then 6.2 g. (0.27 g. atom) of sodium is added in small pieces. When about one-third of the sodium has been added, the white sodium salt of the acid precipitates, and there is strong foaming of the reaction mixture. After all the sodium has been consumed, as evidenced by the disappearance of the blue color, 14.6 g. (0.27 mole) of ammonium chloride is added cautiously. The mixture is stirred for an additional hour and then allowed to stand until the ammonia has evaporated. 

Poly(methyl 3-(l-oxypyridinyl)siloxane) was synthesized and shown to have catalytic activity in transacylation reactions of carboxylic and phosphoric acid derivatives. 3-(Methyldichlorosilyl)pyridine (1) was made by metallation of 3-bromopyridine with n-BuLi followed by reaction with excess MeSiCl3. 1 was hydrolyzed in aqueous ammonia to give hydroxyl terminated poly(methyl 3-pyridinylsiloxane) (2) which was end-blocked to polymer 3 with (Me3Si)2NH and Me3SiCl. Polymer 3 was N-oxidized with m-ClC6H4C03H to give 4. Species 1-4 were characterized by IR and H NMR spectra. MS of 1 and thermal analysis (DSC and TGA) of 2-4 are discussed. 3-(Trimethylsilyl)-pyridine 1-oxide (6), l,3-dimethyl-l,3-bis-3-(l-oxypyridinyl) disiloxane (7) and 4 were effective catalysts for conversion of benzoyl chloride to benzoic anhydride in CH2Cl2/aqueous NaHCC>3 suspensions and for hydrolysis of diphenyl phosphorochloridate in aqueous NaHCC>3. The latter had a ti/2 of less than 10 min at 23°C. 

In the following we shall focus on heterogeneous acid-base reactions. One of the best known case studies is the reaction of crystalline benzoic acid with ammonia to form 1 1 ammonium salts [19, 20]. Crystalline p-chlorobenzoic anhydride reacts with gaseous ammonia to give the corresponding amide and ammonium salt [22] a similar reaction has been investigated in the case of optically active cyclopropanecarboxylic acid crystals [23]. 

Reactions with organic acids such as formic, acetic, benzoic, oxalic, and salicylic acids produce their corresponding ammonium salts concentrated ammonia solution in excess forms ammonium stearate, CH3 (CH2)i6 COONH4 with stearic acid. 

The cyclocondensation of l,3-amino alcohols with carboxylic acid derivatives is a method often applied for the synthesis of 5,6-dihydro-4/7-l,3-oxazines <1996CHEC-II(6)301 >. Ebsorb-4, a weakly acidic zeolite-type adsorbent with 4 A pore size, proved an efficient catalyst of the cyclization of benzoic acid and 3-aminopropanol <2002TL3985>. In the presence of zinc chloride as a catalyst, the expulsion of ammonia drove the reactions of 3-aminopropanol with nitriles to completion, affording 2-substituted 5,6-dihydro-47f-l,3-oxazines in good yields... 

Phenylacetamide has been obtained by a wide variety of reactions from benzyl cyanide with water at 250-260° 6 from benzyl cyanide with water and cadmium oxide at 240° 6 from benzyl cyanide with sulfuric acid 7 8 by saturation of an acetone solution of benzyl cyanide with potassium hydrosulfide 9 from benzyl cyanide with sodium peroxide 10 by electrolytic reduction of benzyl cyanide in sodium hydroxide 11 from ethyl phenyl-acetate with alcoholic 12 or aqueous 13 ammonia from phenyl-acetic acid with ammonium acetate 14 or urea 15 from diazoacetophenone with ammoniacal silver solution 16 from phenyl-acetic acid imino ether hydrochloride and water 17 from acetophenone with ammonium poly sulfide at 215° 18 from benzoic acid 19 and by heating the ammonium salt of phenyl-acetic acid.20... 

The method described is adapted from the procedures of Kym 3 and Engelhardt, Latschinoff, and Malyscheff.4 Thio-benzoic acid has been prepared by the reaction of benzoyl chloride with potassium sulfide,4 hydrogen sulfide in pyridine,6 6 and magnesium bromide hydrosulfide.7 It is formed from dibenzoyl disulfide with potassium hydrosulfide,4 potassium hydroxide,4 8 and ammonia.9 It is also formed from dibenzoyl sulfide, from phenyl benzoate, and from benzoic anhydride with alcoholic potassium hydrosulfide.4 It has been obtained from dibenzoyl sulfide and hydrogen sulfide,10 carbon oxysulfide and phenyl-magnesium bromide,11 12 dibenzyl disulfide and sodium ethoxide,13 benzyl chloride and sulfur in the presence of potassium hydroxide,14 and benzylthiosulfuric acid and alkali.18 16... 

In the reaction of ammonia with l,3,4,5-tetra-0-benzoyl-/3-n-fructopyranose, a significant proportion of benzoic acid was formed, indicating that the ammonolysis of the sugar ester occurred to a certain extent through acyloxy-group rupture. As neither the formation of imidazole nor of pyrazine derivatives (see Section VI,3, p. 124) re-... 

At that time, however, these reactions were not brought to the level of preparative synthesis of nitriles. The main obstacle seemed to be further transformation of the nitriles to acids. In some cases, upon treating al-doximes with alkalies, it was not at all possible to fix nitriles since they immediately converted to acids. The anti(E)-isomers exhibit an enhanced reactivity in these cases. Thus, when boiled in 2 N NaOH, -aldoximes are slowly converted to a mixture of the corresponding carboxylic acids and sy/i(Z)-aldoximes to evolve ammonia (36JA1227). Under these conditions for 4 hr the - and Z-benzaldoximes undergo 13 and 48% conversion to form benzoic acid in 10 and 38% yield, respectively. Analogously, the -and Z-oximes of furfural, under the same conditions for 1.5 hr, are converted to furan-2-carboxylic acid in 33 and 62% conversion and 18 and 49% yield, respectively. 

M. Berthelot. found that many nitrogenous organic compounds furnish ammonia when heated with hydriodic acid and J. Kjeldahl showed that the nitrogen of many nitrogenous compounds is all converted into ammonia or ammonium sulphate when heated with cone, sulphuric acid—in the case of nitro-eompounds and cyanides the reaction is not always quantitative. The reaction proceeds more satisfactorily in the presence of mercury or mercuric oxide, copper, potassium hydrosulphate, sugar, phenol, benzoic acid, and analogous compounds. This reaction has been discussed by C. Arnold, A. Atterberg, C. Budde and C. V. Sehon,... 

The heating of 2-(acylamino)benzoic acids or their alkyl esters with alcoholic ammonia or of ammonium 2-(acylamino)benzoates 5 results in reasonable yields of quinazolin-4(3/F)-ones 6. The reaction probably involves the initial formation of a 2-(acylamino)benzamide which is not... 

The reduction of benzoic acids affords the dienolate (77) which may be alkylated in situ by a variety of electrophiles to afford 1-substituted derivatives. Clearly, the addition of alcohol must be avoided or limited to small quantities. It may also be necessary to remove the ammonia before adding the electrophile. The vast majority of applications have been based on reactions with alkyl halides to form (78), but additions of (77) to formaldehyde, epoxides and a,p-unsaturated esters to form the range of adducts (79) to (81) have also been reported (Scheme 14). 

Episulfoxides. Episulfides are oxidized to episulfoxides by perbenzoic acid in methylene chloride (—20 to —30° 40-75% yield). The simultaneously formed benzoic acid is converted into the ammonium salt by reaction with dry ammonia and removed by filtration.1 Sodium metaperiodate had been used previously for lliis oxidation, but yields were lower.2... 

Liquid ammonia (600 mL) is condensed into a 2-L three-necked round-bottomed flask equipped with a dry ice/acetone condenser fitted with a calcium chloride guard tube, and a mechanical stirrer. The flask is kept at 198 K by a cooling bath (dry ice/acetone mixture). Benzoic acid (38.65 g, 0.32 mol) is placed into a 250-mL round-bottomed flask and dry and freshly distilled ethanol (150 mL) is added. This solution is transferred into the ammonia solution by means of a cannula. Small pieces of sodium metal (21.7 g, 0.94 mol), which are kept under hexane, are added to the reaction mixture with rapid stirring over a period of 30 min. The reaction mixture turned dark blue and is stirred further for about 25 min. Then NH4CI (35 g) is added. The color is discharged within about 2 min. The reaction mixture is stirred for a further hour, the cold bath is removed, and the ammonia left to evaporate under N2 flow and allowed to reach ambient temperature overnight. The white solid in the vessel is dissolved in chilled distilled water (500 mL), which is then acidified by a slow and careful addition of cone, hydrochloric acid (ca. 11 M) to pH 1-2. 

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