1 Bromo-benzoic acid

Benzoic acid, o-bromo- (8) Benzoic acid, 2-bromo- (9) (88-65-3) Copper(I) bromide Copper bromide (CuBr) (8,9) (7787-70-4) Sodium hydride (8,9) (7646-69-7)... 

Benzoic acid, 4,4 -azobis-, diethyl ester-[72 50-68-2], 56, 75 Benzoic acid, 2-benzoyl-, methyl ester-[606-28-0, 21204-86-4], 56, 63 Benzoic acid, o-bromo-[ 88-65-3 ], 58, 56 Benzoic acid, 2-bromo-[88-65-3], 58, 52, 54,56... 

Bromoresorcinol has been prepared by the monobromination of resorcinol monobenzoate and subsequent hydrolysis, from 2-bromo-5-aminophenol by the diazo reaction, by treating resorcinol with dichlorourea and potassium bromide, and by the bromination of 2,4-dihydroxy benzoic acid followed by decarboxylation. The above procedure is based particularly upon the observations of Rice. ... 

Benzoic m-Toluic (Benzoic acid, 3-methyl-] p-Toluic [Benzoic acid, 4-methyl-J 3,5-Dimcthylbcnzoic [Benzoic acid, 3,5-dimcthyl-] p-Chlorobenzoic [Benzoic acid, 4-chloro-] p-Bromobenzoic [Benzoic acid, 4-bromo-J Phthalic [ 1,2-Bcnzcncdicarboxylic acid] Toluene [Benzene, methyl-] (78) m-Xylene [Benzene, 1,3-dimethyl-] (82) />-Xylene [Benzene, 1,4-dimethyl-] (74) Mesitylene [Benzene, 1,3,5-trimethyl-] (82) p-Chlorotolueno [Benzene, l-ehloro-4-methyl-] (94) p-Bromotolucnc [Benzene, l-bromo-4-methyl-] (94) o-Xylene [Benzene, 1,2-dimethyl-] (64)... 

Benzoic acid, 2-benzoyl-, methyl ester [606-28-0,21204-864], 63 Benzoic acid, 4-bromo- [586-76-5], 86 Benzoic acid, 4-chloro- [74-11-3], 86 Benzoic acid, 2-[(diethylamino)carbonyl]-, methyl ester [2659344-2], 63 Benzoic acid, 2,4-dimethoxy- [91-52-1 ], 31 Benzoic acid, 3,4-dimethoxy- [93-07-2], 31 Benzoic acid, 3,4-dimethyl- [619-04-5], 31 Benzoic acid, 3,5-dimethyl- [499-06-9], 86 Benzoic acid, 4-hydroxy- [99-96-7], 60 Benzoic acid, 3-methyl- [99-04-7], 86 Benzoic acid, 4-methyl- [99-94-5], 86 Benzoic acid, 2,4,6-tnmethyl- [480-63-7],... 

Malonic acid, amino-, diethyl ester, HYDROCHLORIDE, 40, 24 Malonic acid, bts(hydroxymethyl)-, DIETHYL ETHER, 40, 27 Malonitrile, condensation with tetra-cyanoethylene, 41, 99 2-Mercaptopyrimidine, 43, 6S hydrochloride of, 43, 68 Mercuric oxide in preparation of bromo-cyclopropane, 43, 9 Mesityl isocyanide, 41,103 5-Methallyl-l,2,3,4,5-pentachlorocyclo-pentadiene, 43, 92 Methane, dimesityl-, 43, 57 Methanesiileinyl chloride, 40, 62 Methanesulfonic acid, solvent for making peroxybenzoic acid from benzoic acid, 43, 93... 

A rapid MW-assisted palladium-catalyzed coupling of heteroaryl and aryl boronic acids with iodo- and bromo-substituted benzoic acids, anchored on TentaGel has been achieved [174]. An environmentally friendly Suzuki cross-coupling reaction has been developed that uses polyethylene glycol (PEG) as the reaction medium and palladium chloride as a catalyst [175]. A solventless Suzuki coupling has also been reported on palladium-doped alumina in the presence of potassium fluoride as a base [176], This approach has been extended to Sonogashira coupling reaction wherein terminal alkynes couple readily with aryl or alkenyl iodides on palladium-doped alumina in the presence of triphenylphosphine and cuprous iodide (Scheme 6.52) [177]. 

Benzene-l,4-diols are oxidized to quinones by benzyltrimethylammonium tribromide under mild conditions in almost quantitative yields [6]. With an excess of the tribromide further reaction produces the 2-bromo-l, 4-quinones. This oxidation is in contrast to the analogous reaction of phenols, which produces bromophenols (see Section 2.3). Hindered 4-methyl-phenols are oxidized to the corresponding benzyl alcohols, benzaldehydes, bromomethyl derivatives and 4-bromo-4-methylcyclo-hexa-2,5-dien-l-ones [7]. Benzylic alcohols are oxidized under neutral or basic conditions to yield the corresponding aldehydes (>70%) oxidation with an excess of the reagent produces the benzoic acids (>90%) [8],... 

Uses Intermediate in production of styrene, acetophenone, ethylcyclohexane, benzoic acid, 1-bromo-l-phenylethane, 1-chloro-l-phenylethane, 2-chloro-l-phenylethane, p-chloroethylbenz-ene, p-chlorostyrene, and many other compounds solvent in organic synthesis. 

Regioselectivity in the exchange of formally equal halogens can be found also outside the heterocyclic series. Inductive effects appear to be the controlling factor. For example, 3,3, 5-tribromodibenzyl ether (l,3-dibromo-5-[(3-bromophenyhnethoxy)methyl]benzene 5) is exclusively converted into 3-bromo-5-[(3-bromophenylmethoxy)methyl]benzoic acid (equation 3) when treated consecutively with butyUithium in tetrahydrofuran at —75 °C and dry ice. 

Bromo- and iodoanihnes, -phenols and -benzoic acids are first deprotonated in situ by an excess of the organomagnesinm reagent and then coupled (PdCl2(dppf), 1 mol%, THF, 25 °C, 3 h) with organomagnesium halides, thus avoiding tedious protection-deprotection steps . Iron(in) salts can also serve as appropriate catalysts for varions cross-coupling... 

A clever application of this reaction has recently been carried out to achieve a high yield synthesis of arene oxides and other dihydroaromatic, as well as aromatic, compounds. Fused-ring /3-lactones, such as 1-substituted 5-bromo-7-oxabicyclo[4.2.0]oct-2-en-8-ones (32) can be readily prepared by bromolactonization of 1,4-dihydrobenzoic acids (obtainable by Birch reduction of benzoic acids) (75JOC2843). After suitable transformation of substituents, mild heating of the lactone results in decarboxylation and formation of aromatic derivatives which would often be difficult to make otherwise. An example is the synthesis of the arene oxide (33) shown (78JA352, 78JA353). 

The fluorination of other activated aromatic compounds, such as anisole and phenol, undergo monofluorination mainly in the ortho and para positions, whereas the fluorination of deactivated aromatics, such as nitrobenzene, trifluoromethylbenzene and benzoic acid, give predominantly the corresponding meta fluoro-derivatives which is consistent with a typical electrophilic substitution process. Also, fluoro-, chloro- and bromo-benzenes are deactivated with respect to benzene itself but are fluorinated preferentially in the ortho and para positions [139]. At higher temperatures, polychlorobenzenes undergo substitution and addition of fluorine to give chlorofluorocyclohexanes [136]. 

Carbonylation of Halides - Pd(tppts)3-catalysed carbonylation of bromo-benzene (Equation 7) in the presence of NEt3 in an aqueous/toluene (1/1) two phase system at 150°C and 15 bar CO afforded the triethylammonium salt of benzoic acid (100% yield).464,465 Rates were rather low (TOF s of 3.3-17 h ) but no decomposition of Pd(tppts)3 (tppts/Pd 12.5) was observed and the catalyst could be recovered quantitatively and recycled 464 However, in a second recycle extensive decomposition of the catalyst occurred with formation of palladium black. Generally in carbonylation reactions of halides the formation of stoichiometric amounts of either HX or halide salts still remains a problem of environmental concern despite the attractiveness due to the presence of the aqueous solvent. 

The original racemic patents described the use of resolution to give a chiral oxirane, such as 25, as an intermediate or the use of a chiral auxiliary (20) to produce the salmeterol enantiomers. Alkylation of chiral amine 20 with 2-benzyloxy-5-(2-bromo-acetyl)-benzoic acid methyl ester, followed by diastereoselective reduction of the ketone with lithium borohydride furnished intermediate 21 after chromatographic separation of the diasteromers. Removal of the benzyl group and the chiral auxiliary was... 

Lithium o-lithiobcnzoate (1). The reagent is prepared by treatment of o-bromo-benzoic acid with n-bulyllilhium in THF at —1000.1... 

Substituent effects on the A,u I reaction have been studied by Bender and Chen55. These authors measured the rates of hydrolysis of a series of 4-substituted 2,6-dimethylbenzoates in 9.70 M sulphuric acid at 25°C, and found that the values for the first-order coefficients with 4-methoxy, 4-methyl, 4-unsubstituted and 4-bromo-compounds (5.0, 0.37, 0.033 and 0.01 x I0 4 sec-1, respectively) are satisfactorily correlated by the Hammett equation, following cr+ with a slope p = —3.22. Since the esters are not fully protonated in 9.70 M H2SOj, part of this factor is due to the effects of the 4-substituent on the protonation equilibrium, p for the protonation of substituted benzoic acids is about — l35, but is likely to be considerably smaller for di-ortho-substituted compounds, since the conjugative interaction of the p-substituents with the protonated carboxyl group requires coplanarity with the ring. 

Methanolysis of penta-0-benzoyl-5-bromo-/ -D-glucopyranose, using silver oxide and methanol, gives a complex set of products, but hydrolysis in the presence of this solid affords the 5-hydroxy analog 128 which, in aqueous media, equilibrates with the 5-ulose 129 this loses benzoic acid, and the resulting aldehyde recyclizes, to afford 2,3,4,6-tetra-0-benzoyl-5-hydroxy-/ -D-glucose (130) (see Scheme 21).26... 

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