Phenyl 2-aminobenzoate

Intramolecular general base-catalyzed water attack has also been observed for phenyl 2-aminobenzoate. ... 

The hydrolysis of phenyl 2-aminobenzoate is pH dependent. The reaetion follows a pseudo-first order rate law and the plot of log obs versus pH shows OH eataly-sis at pH > 9 and a large pH independent region between pH 4 and pH 8.5. The plot bends downward near pH 4 to give a slope of 1.0. The downward bend eorre-sponds with the pifa of the amino group (Fig. 23.1). 

Perhaps the most striking feature of flie plot of log obs versus pH for flie hydrolysis of phenyl 2-aminobenzoate 1 (Fig. 23.1) is the large pH-independent region extending from pH 4 to 8.5. At higher pH values flie reaction rate increases due to the base (OH ) catalysis. However, near pH 4 (die of the amino group),... 

The importance of the free amino group in the process also comes across when comparing the rate constants of hydrolysis of phenyl benzoate and phenyl 2-aminobenzoate 1 in the same pH 4-8.5 range. As depicted in Fig. 23.2, the hydrolysis of phenyl benzoate is considerably slower than that of 1. As both esters only differ by the presence of the amino group in the aromatic ring, the differences in reaction rates again point to the involvement of the amino group in the reaction. 

Interestingly, the hydrolysis of phenyl 2-aminobenzoate 1 is much faster than the hydrolysis of phenyl 4-amino benzoate. This suggests that to be involved in the process, the amino group must be placed at the ortho position of the aromatic ring. 

Direct cyclization of a related aminothiophene (48) occurred on treatment with phosphorus oxychloride to give 49,52 and ring closure between the thiophene ring and the side chain in the p-nitrophenyl-hydrazones (50) with polyphosphoric acid yielded 51. On heating, 2,3-diacetamidobenzo[ft]thiophene eliminated acetic acid and water to give 2-methylbenzothieno[2,3-d]imidazole (52),54,JJ but successful conditions could not be found for cyclization of 2-acetamido-3-phenyl-aminobenzo[6]thiophene.55... 

A mixture 31.3 g of o-chlorobenzoic acid, 32.2 g of trifluoromethyl-m-aminobenzene, 3 g of copper powder, 13.8 g of waterless potassium carbonate and 100 ml amyl alcohol was refluxed for 4 hours. To the cooled mixture was added 25 ml of 10 N solution NaOH and the mixture was concentrated and filtrated. Addition to the filtrate hydrochloric acid and water give a sediment of 2-((3-trifluromethyl)phenyl)aminobenzoic acid. After recrystallization from hexane 2-((3-trifluromethyl)phenyl)aminobenzoic acid have melting point 134-136°C. 

Through systematic modification of the imidazole-appended 2-phenyl-aminobenzoate peptidomimetic scaffold (e.g., FTI-2148) a group at Abbott Pharmaceuticals have identified an expanded series of inhibitors that lack either the C-terminal Met carboxylate (as in compounds 14-23 of Ref. [55]) or the imidazole group (as in ABT-839) [56,70,71]. This latter compound became a clinical candidate and demonstrates that coordination to the zinc ion is not a prerequisite for potent inhibitors of FT. In place of metal-ligand (imidazole, thiol, etc.) coordination, ABT-839 exploits hydrophobic contact from the cyclohexylethyl and -butyl groups to the protein-binding pocket. For the structures of other CaaX peptidomimetics, please refer to Table 6.1. 

Successful results have been obtained (Renfrew and Chaney, 1946) with ethyl formate methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec.-butyl and iso-amyl acetat ethyleneglycol diacetate ethyl monochloro- and trichloro-acetates methyl, n-propyl, n-octyl and n-dodecyl propionates ethyl butyrate n-butyl and n-amyl valerates ethyl laurate ethyl lactate ethyl acetoacetate diethyl carbonate dimethyl and diethyl oxalates diethyl malonate diethyl adipate di-n-butyl tartrate ethyl phenylacetate methyl and ethyl benzoates methyl and ethyl salicylates diethyl and di-n-butyl phthalates. The method fails for vinyl acetate, ieri.-butyl acetate, n-octadecyl propionate, ethyl and >i-butyl stearate, phenyl, benzyl- and guaicol-acetate, methyl and ethyl cinnamate, diethyl sulphate and ethyl p-aminobenzoate. 

Perfumes, Flavors, Cosmetics, and Soap. Many naturally occurring esters in essential oils and some synthetic esters are important fragrance and flavor compounds (61,62). They are used in perfumes, flavors, cosmetics, soaps, detergents, and air fresheners. Benzyl, butyl, ethyl, methyl, and phenyl esters of benzoic acid are used as flavors, perfumes, and food preservatives. Glyceryl 4-aminobenzoate [136-44-7] and 2-ethyUiexyl 4-dimethylaminobenzoate [21245-02-3] are used in cosmetic sunscreen preparations. Alkyl esters of 4-hydroxybenzoic acid, called parabens, have been used under various names for fungus infections of the skin, and as preservatives in lotions and creams (101). Soap and cosmetic fragrances use large amounts of amyl and benzyl saHcylate. Benzyl saHcylate [118-58-1] is also used in deodorant sprays. 2-Ethylhexyl saHcylate [118-60-5] and 2-ethylhexyl 4-methoxycinnamate [5466-77-3] are used in sunscreen formulations (102). 

Medicinals. Many esters are used as pharmaceuticals (105,106). Of these, benzocaine, ethyl 4-aminobenzoate [94-09-7] is a topical anesthetic. Phenyl saHcylate [118-55-8] (1) has antipyretic, antirheumatic, and antiparasitic properties. 

Likewise, thermolysis of 4-azidophenyl methyl ketone in methanol yields 5-acetyl-2-methoxy-3//-azepine (60%), compared to only an 8% yield from the photolytic reaction.78 119 The thermolysis of phenyl azide in refluxing cyclohexanol yields no 3H-azepine, only diphenyl-diazene (10%) and aniline (30%).74 In contrast, thermolysis of methyl 2-azidobenzoate in cyclohexanol furnishes a mixture of methyl 2-(cyclohexyloxy)-3//-azepine-3-carboxylate (20 % bp 127°C/0.1 Torr) and methyl 2-aminobenzoate (60%). Thermolysis of the azido ester in methanol under nitrogen in an autoclave at 150 C yields a 7 10 mixture (by 1HNMR spectroscopy) of the amino ester and methyl 2-methoxy-3//-azepine-3-carboxylate, which proved to be difficult to separate, and much tar.74 The acidic medium179 is probably responsible for the failure of methyl 2-azidoberjzoate to yield a 3//-azepine when thermolyzed in 3-methoxyphenol aniline (40%) is the major product.74... 

Attempts to effect ring expansion of methyl 2-azidobenzoate in the presence of other nucleophiles have failed. Thus, photolysis in tetrahydrofuran solution saturated with hydrogen sulfide, or with ammonia, produced methyl 2-aminobenzoate in 54 and 37 % yield, respectively, as the sole identifiable product.197 Photolysis of phenyl azide in ethanolic phenol gave 2-phenoxy-3//-azepine in poor yield (8 %).203,204 2-Mesityl-3//-azepine (10 %) is the surprising, and only tentatively explained, product from the photolysis of phenyl azide in mcsitylene in the presence of trifluoroacetic acid.179... 

In a sequence of cycloaddition and cycloreversion, 3-phenyl-l, 2,4-triazine 1-oxides react with benzyne, generated from 2-aminobenzoic acid (see Houben-Weyl, Vol. 5/2 b, p 622 ff), to give 2-phenyl-l, 3-benzoxazepines in moderate yield.419... 

Heating phenacyl 2-aminobenzoate with phosphoryl chloride yields 2-phenyl-4,1-benz-oxazepin-5(17/)-one (1. R = H). The method has been applied to the synthesis of a number of analogs.423... 

This category is represented in the facile reaction of o-phenylenediamine (408) with 4-benzoyl-5-phenyl-2,3-dihydro-2,3-thiophenedione (409) (in toluene at 20°C for 30 min) to afford 3-(a-benzoyl-p-mercaptostyryl)-2(l//)-qumoxalinone (410) in 98% yield " also in the complicated reaction of 3-methyl-2,2,4-trinitro-2,5-dihydrothiophene 1,1-dioxide (411) with 2 equiv of ethyl 4-aminobenzoate (412) (in acetonitrile but no further details) to give ethyl 2-(p-ethoxycarbonylphenyl)-3-(l-methyl-2-nitrovinyl)-6-quinoxalinecarboxylate (413) in 51% yield.Several... 

In the presence of the reactive initiator phenyl p-nitrobenzoate 2198 phenoxy-trimethylsilane 13d is ehminated in the CsF/18-crown-6 catalyzed polymerization of silylated phenyl p-N-(n-octyl)aminobenzoate 2199 in THF to form the polymer 2200 [12] (Scheme 14.4). 

Chem. Abstr. Name 3-Phenyl-2-propen-l-ol, 2-aminobenzoate lUPAC Systematic Name Anthranilic acid, cinnamyl ester Synonyms Cinnamyl alcohol anthranilate 3-phenyl-2-propenyl 2-aminobenzoate 3-phenyl-2-propenyl anthranilate... 

Problem 18.49 Outline the steps in the syntheses of the following compounds from C H, C HjCH, and any readily available aliphatic compound (a) p-aminobenzoic acid, (b) m-nitroacetanilide, (c) 1-amino-l-phenyl-propane, (d) 4-amino-2-chlorotoluene. M... 

Phenol Antimicrobial preservative disinfectant (not oral) Camphor, menthol, thymol, acetaminophen, phenacetin, chloral hydrate, phenazone, ethyl aminobenzoate, methenamine, phenyl salicylate, resorcinol, terpin hydrate, sodium phosphate, or other eutectic formers. Phenol also softens cocoa butter in suppository mixtures... 

Hydroxybenzo[6]thiophene has been isolated from coal tar.42 It may be prepared from 6-aminobenzo[fr]thiophene by standard procedures.241 6-Methoxybenzo[h]thiophene may be prepared by decarboxylation of the corresponding 2-carboxylic acid,341 and 6-ethoxybenzo[6]thiophene is obtained by reduction of 6-(ethoxy)-thioindoxyl (Section VI, 1,2). 6-Methoxy-5-methylbenzo[6]thiophene is obtained by cyclization of (3-methoxy-4-methylphenylthio)-acetaldehyde dimethyl acetal (Section IV,B).617 The product previously described542 as 6-hydroxy-3-phenylbenzo[6]thiophene has now been shown to be the 2-phenyl isomer.307 6-Methoxy-818 and 6-methoxy-5-methyl-benzo[6]thiophene617 are demethylated by pyridine hydrochloride. 

Aminobenzoic acid Gel HPLC Dissolve sample and Phenyl (LI 1). MeOH-AcOH-H 0 (30 280 nm enantiomers [142] parenterals [144] USP 23, p. 83, assay [5]... 

SYNS 2-AMINOBENZOIC ACID-3-PHENYL-2-PROPENYL ESTER CINNAMYL ALCOHOL ANTHRANILATE CINNAMYL-o-Ai QNO-BENZOATE... 

Raney nickel) of the potassium salt of D-xy/o-5-hexulosonic acid oxime produces a mixture of 5-amino-5-deoxy-L-idonic and -D-glu-conic acid in the ratio of 2 1, which is converted into the methyl ester hydrochloride. Upon treatment with alkali, spontaneous cyclization to the pair of 1,5-lactams occurs. 5-Amino-5-deoxy-L-idono-l,5-lactam and 5-amino-5-deoxy-D-glucono-l,5-lactam were separated by recrystallization. The optical rotatory dispersion curves of both compounds were discussed. A new type of lactam, namely, 2-enamino-N,N -bis[(p-methoxycarbonyl)phenyl]-4-(D-gaiacfo-penta-acetoxypentyl)-4-butanelactam was prepared by tbe reaction of 5,6,7,8,9-penta-0-acetyl-3,4-dideoxy-D-ga/ocfo-nonulos- rcns-3-en-l-onic acid with methyl p-aminobenzoate. 

C9H10O5 2 hydroxy-2-(4-hydroxy-3-methoxy-phenyl)-ace 2394-20-9 493.15 43.226 2 16929 C9H11N02 ethyl 4-aminobenzoate 94-09-7 583.15 51.928 1,2... 

A somewhat different mechanism was deduced by Baker and Bailey 4f) from their own studies of the systems phenyl isocyanate and ethyl p-aminobenzoate (benzocaine) cyclohexyl isocyanate and aniline phenyl isocyanate and aniline p-methoxyphenyl isocyanate and aniline. While Craven postulates one complex. Baker and Bailey assume two complexes of the isocyanate one with the amine, and one with the product urea. 

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