Of 2,4-dichlorobenzoic acids

Romanov V, RP Hausinger (1996) NADPH-dependent reductive ortho dehalogenation of 2,4-dichlorobenzoic acid in Corynebacterium sepedonicum KZ-4 and coryneform bacterium strain NTB-1 via 2,4-dichlo-robenzoyl coenzyme A. J Bacteriol 178 2656-2661. 

Quinacrine Quinacrine, 6-chloro-9-(4-diethylamino-l-methylbntylamino)-2-methoxy-acridine (37.1.4.3), is synthesized from 6,9-dichloro-2-methoxyacridine (37.1.4.2) and aforementioned 4-diethylamino-l-methylbutylamine (37.1.1.2). The 6,9-dichloro-2-methoxyacridine (37.1.4.2) necessary for the synthesis is made in two stages. The initial reaction of 2,4-dichlorobenzoic acid and p-anizidine in the presence of copper dnst and potassium carbonate gives 2-(4-methoxyanilino)-4-chlorobenzoic acid (37.1.4.1), which upon reaction with phosphorus oxychloride turns into the necessary 6,9-dichloro-2-methoxyacridine (37.1.4.2) [33-38]. 

Benzoylthiourea-pyrrolidine (101), derived from L-proline, efficiently catalyses Michael addition of cyclohexanone to nitrostyrenes delee values of over 98/99% have 0 been achieved in the presence of 2,4-dichlorobenzoic acid as co-catalyst. 0... 

Also obtained by condensation reaction of hydroquinone dimethyl ether with excess of 2,4-dichlorobenzoic acid in the presence of polyphosphotic acid [1251]. 

Diuretics are drugs that increase the excretion of urine by the kidney, thereby decreasing body fluids. This alleviates the swelling of tissues that sometimes cause high blood pressure and heart, kidney, and liver failure. Furosemide is the most effective diuretic. It inhibits the readsorption of sodium in the kidney and promotes potassium excretion, two ions intimately involved in water retention for the body. It lowers blood pressure as well. The starting material for its synthesis is 2,4-dichlorobenzoic acid (formed by... 

The preparation of the A -desmethyl analogue, amoxapine (39-7), illustrates an alternate approach in which the oxygen ether linkage is formed last. Reaction of the imidazolide (39-2) from 2,4-dichlorobenzoic acid (39-1) and carbonyldiimidazole with ort/zo-aminophenol (39-3) gives the benzamide (39-4). This is then converted to its imino chloride (39-5) with the ubiquitous phosphorus oxychloride. Treatment of the product with piperazine leads to the amidine (39-6), probably by an addition-elimination sequence. Copper catalyzed displacement of chlorine by phenoxide closes the ring there is thus obtained amoxapine (39-7) [40]. 

Furosemide can also be synthesized starting with 2,4-dichlorobenzoic acid (formed by chlorination and oxidation of toluene). Reaction with chlorosulfonic acid is an electrophilic aromatic substitution via the species -S02C1 attacking ortho and para to the chlorines and meta to the carboxy-late. Ammonolysis to the sulfonamide is followed by nucleophilic aromatic substitution of the less hindered chlorine by furfurylamine (obtained from furfural—a product obtained by the hydrolysis of carbohydrates). 

Quinacrine may be easily prepared starting form 2,4-dichlorobenzoic acid (90). Ullmann reaction of 90 with p-anisidine (91) gives the desired diphenylamine 92, which is cyclised to form the 9-chloroacridine derivative (93). Condensation of the latter with l-diethylamino-4-aminopentane affords quinacrine (22) [71]. A similar sequence of reaction starting from 90 and 5-amino-2-methoxypyridine (94) gives azocrine (28) [72] (Scheme 3). 

Nomenclature of Carboxylic Acids Section 12.2A (a) 2,4-dichlorobenzoic acid (b) p-nitrobenzoic acid ... 

Numerous individual substances were detected only in Ru04 extracts e.g. di- to pentachlorinated benzenes, 4-chlorobenzoic acid and 2,4-dichlorobenzoic acid 24, hexachlorocyclohexanes (a-,P-,y- and 5-HCH) 22, a technical mixture obtained during the synthesis of lindane, and the plasticizers alkylsulfonic acid phenylesters 23. These plasticizers were recently identified in riverine sediments (Franke et al. 1998). Furthermore, nitro-substituted benzoic acid and alkylated phenols 24 were observed. The occurrence of aromatic nitro compounds as a result of the oxidation of anilines can be excluded due to the contemporary appearance of amino compounds, e.g. 4-aminobenzoic acid or N-ethylaniline. However, the origin as well as the emission pathway of these compounds is still unknown. 

Dichloro-5-sulphamoyl benzoic acid may be prepared by reacting 2,4-dichlorobenzoic acid with chlorosulphonic acid at an elevated temperature and then carrying out the amidation. This on treatment with furfuryl amine in the presence of sodium bicarbonate, affords nueleophilie aromatie displacement of the highly activated chlorine at C-2, thereby yielding furosemide. However, the proteetion of the chlorine atom at C-4 may be achieved by regulating the temperature of the furfuiylamination. 

Both, l,3-dimethyl-5-pyrazolon (9) and 2,4-dichlorobenzoic acid are commercial available, which allows a few steps synthesis of pyrazolynate. However, owing to the high application rate of 3-4 kg ha , the treatment costs are very high. In theory the application rate could be lower by using the drug 4-(2,4-dichlorobenzoyl)- ,3-dimethyl-5-hydroxypyrazole (8) instead of the prodrug. Another important factor for the Japanese rice market is season-long weed control of a herbicide, which is not possible with the more polar and more water-soluble... 

Chlorinated benzoic acids have been shown to be intermediates in the biodegradation of several chlorinated aromatic compounds, for example, 4-chlorobenzoic acid is formed in the biodegradation of both polychlorinated biphenyls [103]. Mixed microbial cultures, which have been studied by a number of groups under aerobic conditions, can degrade a wide range of chlorinated benzoic acids, including 2-, 3- and 4-chlorobenzoic acid as well as 3,4-dichloro- and 2,4-dichlorobenzoic acid [104]. By contrast, under anaerobic conditions, only reductive dechlorination of meta-substituted benzoic acids has been observed [49,105,106]. Cometabolism of chlorobenzoic acids in the presence of unsubstituted benzoic adds leads to the formation of the corresponding... 

When the anion is reacted with 4-chlorobenzoic acid methylester only a 10% yield is observed. With 2,4-dichlorobenzoic acid methylester none of the expected ketone is obtained. The reason for this failure to obtain satisfactory yields of chlorinated ketones by this procedure has not been investigated. 

Preparation by reaction of 2,4-dichlorobenzo-trichloride with m-cresol in hydrofluoric acid in the presence of water at -10°, then at 15° overnight and at 80° for 30 min (87%) [213]. 

Preparation by total demethylation of 2, 6 -dichloro-4,5-di-methoxy-2-methylbenzophenone (SM) [1072], with pyridinium chloride for 2 h at 180-200° [1199], SM was obtained by reaction of 2,6-dichlorobenzoic acid with 1,2-dimethoxy -methylbenzene in the presence of phosphorous pentoxide in methanesulfonic acid for 30 min at 70° [1199], Preparation by Friedel-Crafts acylation of 4-methylpyrocatechol with 2,6-dichlo-robenzoyl chloride [1072]. 

Thirty-eight grams (0.1 mole) of bis-3,4-dichlorobenzoyl peroxide (Note 1) is added to a boiling solution of 3 g. of >re-dinitro-benzene in 800 ml. of dry reagent grade benzene contained in a 1-1. round-bottomed flask, and the resulting solution is boiled under reflux for 40 hours. The solvent is then distilled from the red solution until the residual volume is about 200 ml. (Note 2), and the mixture is allowed to cool. The 3,4-dichlorobenzoic acid... 

Less reactive than acyl halides, but still suitable for difficult couplings, are symmetric or mixed anhydrides (e.g. with pivalic or 2,6-dichlorobenzoic acid) and HOAt-derived active esters. HOBt esters smoothly acylate primary or secondary aliphatic amines, including amino acid esters or amides, without concomitant esterification of alcohols or phenols [34], HOBt esters are the most commonly used type of activated esters in automated solid-phase peptide synthesis. For reasons not yet fully understood, acylations with HOBt esters or halophenyl esters can be effectively catalyzed by HOBt and HOAt [3], and mixtures of BOP (in situ formation of HOBt esters) and HOBt are among the most efficient coupling agents for solid-phase peptide synthesis [2]. In acylations with activated amino acid derivatives, the addition of HOBt or HOAt also retards racemization [4,12,35]. 

Ch loro- 3.5- Dinitrobenzoic acid 2.5- Dichlorobenzoic acid Chlamydomonas sp. A2 By consortia of bacteria... 

---