Sulfonic acids hydrolysis

Pyrimidine-4-sulfonic acid, 2,6-dimethyl-reactions, 3, 97 Pyrimidinesulfonic acids acidic pif 3, 60 reactions, 3, 96 synthesis, 3, 138 Pyrimidine-2-sulfonic acids acidic pK, 3, 60 reactions, 3, 97 Pyrimidine-4-sulfonic acids hydrolysis, 3, 97 Pyrimidine-2-sulfonyl chloride synthesis, 3, 138... 

Naphthalenols, naphthalenediols, and their sulfonated and amino derivatives are important intermediates for dyes, agricultural chemicals, drugs, perfumes, and surfactants. The methods of manufacture include caustic fusion of naphthalene-l-sulfonic acid, hydrolysis of 1-chloro- or... 

Even ia 1960 a catalytic route was considered the answer to the pollution problem and the by-product sulfate, but nearly ten years elapsed before a process was developed that could be used commercially. Some of the eadier attempts iacluded hydrolysis of acrylonitrile on a sulfonic acid ion-exchange resia (69). Manganese dioxide showed some catalytic activity (70), and copper ions present ia two different valence states were described as catalyticaHy active (71), but copper metal by itself was not active. A variety of catalysts, such as Umshibara or I Jllmann copper and nickel, were used for the hydrolysis of aromatic nitriles, but aUphatic nitriles did not react usiag these catalysts (72). Beginning ia 1971 a series of patents were issued to The Dow Chemical Company (73) describiag the use of copper metal catalysis. Full-scale production was achieved the same year. A solution of acrylonitrile ia water was passed over a fixed bed of copper catalyst at 85°C, which produced a solution of acrylamide ia water with very high conversions and selectivities to acrylamide. 

Manufacture of Fatty Acids and Derivatives. Splitting of fats to produce fatty acids and glycerol (a valuable coproduct) has been practiced since before the 1890s. In early processes, concentrated alkaU reacted with fats to produce soaps followed by acidulation to produce the fatty acids. Acid-catalyzed hydrolysis, mostly with sulfuric and sulfonic acids, was also practiced. Pressurized equipment was introduced to accelerate the rate of the process, and finally continuous processes were developed to maximize completeness of the reaction (105). Lipolytic enzymes maybe utilized to spHt... 

Although catalytic hydration of ethylene oxide to maximize ethylene glycol production has been studied by a number of companies with numerous materials patented as catalysts, there has been no reported industrial manufacture of ethylene glycol via catalytic ethylene oxide hydrolysis. Studied catalysts include sulfonic acids, carboxyUc acids and salts, cation-exchange resins, acidic zeoHtes, haUdes, anion-exchange resins, metals, metal oxides, and metal salts (21—26). Carbon dioxide as a cocatalyst with many of the same materials has also received extensive study. 

Hydroxynaphthalenesulfonic acids are important as intermediates either for coupling components for a2o dyes or a2o components, as well as for synthetic tanning agents. Hydroxynaphthalenesulfonic acids can be manufactured either by sulfonation of naphthols or hydroxynaphthalenesulfonic acids, by acid hydrolysis of arninonaphthalenesulfonic acids, by fusion of sodium naphthalenepolysulfonates with sodium hydroxide, or by desulfonation or rearrangement of hydroxynaphthalenesulfonic acids (Table 6). 

Both 5-hydroxyquiQoline [578-67-6] and S-hydroxyquiaoline [148-24-3] have been prepared ia good yields by the acid hydrolysis of the appropriate aminoquiaoline at temperatures of 180—235°C (124). The latter compound has been prepared ia several different ways, including sulfonation-fusion of quiaoline. Hydrolysis of 8-chloroquinoline [611-33-6] gives a 93% yield, whereas 80% is obtained ia a modified Skraup synthesis with o-aminophenol (125,126). 

Orthoesters. The value of cycHc orthoesters as intermediates for selective acylation of carbohydrates has been demonstrated (73). Treatment of sucrose with trimethylorthoacetate and DMF in the presence of toluene-/)-sulfonic acid followed by acid hydrolysis gave the 6-0-acetylsucrose as the major and the 4-0-acetylsucrose [63648-80-6] as the minor component. The latter compound underwent acetyl migration from C-4 to C-6 when treated with an organic base, such as / fZ-butylamine, in DMF to give sucrose 6-acetate in >90% yield (74). When the kinetic reagent 2,2-dimethoxyethene was used,... 

Sulfation is defined as any process of introducing an SO group into an organic compound to produce the characteristic C—OSO configuration. Typically, sulfation of alcohols utilizes chlorosulfuric acid or sulfur trioxide reagents. Unlike the sulfonates, which show remarkable stability even after prolonged heat, sulfated products are unstable toward acid hydrolysis. Hence, alcohol sulfuric esters are immediately neutralized after sulfation in order to preserve a high sulfation yield. 

Two important widely used sulfonic acids are known as TwitcheU s reagents, or as in Russia, the Petrov catalysts. These reagents are based on benzene or naphthalene ( ) and (12), [3055-92-3] and [82415-39-2] respectively. The materials are typically made by the coupling of an unsaturated fatty acid with benzene or naphthalene in the presence of concentrated sulfuric acid (128). These sulfonic acids have been used extensively in the hydrolysis of fats and oils, such as beef tallow (129), coconut oil (130,131), fatty methyl esters (132), and various other fats and oils (133—135). TwitcheU reagents have also found use as acidic esterification catalysts (136) and dispersing agents (137). 

Tetrachlorotoluene, C H Cl (mol wt 229.93) (1,2,3,5-tetrachloro-4-methylben2ene), is prepared from the Sandmeyer reaction on 3-arnino-2,4,6-trichlorotoluene. 2,3,4,5-Tetrachlorotoluene (l,2,3,4-tetrachloro-5-methylben2ene) is the principal isomer in the further chlorination of 2,4,5-trichlorotoluene. Exhaustive chlorination of -toluenesulfonyl chloride, followed by hydrolysis to remove the sulfonic acid group yields... 

The reaction of substituted chloronitrobenzenes with arylamines to form substituted diphenyl amines is typified by 4-rutrodiphenylamine-2-sulfoiiic acid where 4-chloronitrobenzene-3-sulfonic acid (PN salt) is condensed with aniline ia an aqueous medium at 120°C and 200 kPa (2 atm) ia the presence of alkaline buffer at low pH to avoid the competing hydrolysis of the PN salt. 

Acidic Hydrolysis. Hydrolysis of esters by use of water and a mineral acid leads to an equiUbrium mixture of ester, alcohol, and free carboxyHc acid. Complete reaction can only be achieved by removal of alcohol or acid from the equiUbrium. Because esters have poor solubiUty in water, the reaction rate in dilute acids is fairly low. Therefore, emulsifiers such as sulfonated oleic acid or sulfonated aromatic compounds (TwitcheU reagent) are added to facihtate the reaction. 

There are at least eight syntheses of orotic acid in the literature. The most practical in the laboratory is that involving the condensation of diethyl oxalacetate (972) with S-methylthiourea to give 2-methylthio-6-oxo-l,6-dihydropyrimidine-4-carboxylic acid (973) which undergoes either direct acidic hydrolysis or a less smelly oxidative hydrolysis, via the unisolated sulfone (974), to afford orotic acid (971) (B-68MI21303). 

Pyrazolesulfonic acids, like (493), have high melting points (Table 24) and probably exist as the zwitterions (497). They are very stable to hydrolysis and only afford pyrazolones at high temperatures. The replacement of the SO3H group by bromine has also been reported (B-76MI40402). Pyrazole-3-, -4- and -5-sulfonic acids react with phosphorus pentachloride to form sulfonyl chlorides. 

To prepare alkylhydrazlnes, cyclohexanone is treated with a primary amine and hydroxyl-amine-O-sulfonic acid in a one-pot procedure hydrolysis to the alkylhydrazine is carried out without isolation of the diaziridine (68JPR(37)257). Yields are between 60 and 70%. 

Hydrolysis of esters is speeded up by both acids and bases. Soluble aflcylaiyl sulfonic acids or sulfonated ion exchange resins are suitable. 

Compounds i, ii, and iii can be prepared by an acid-catalyzed reaction of a diol and the cycloalkanone in the presence of ethyl orthoformate and mesitylene-sulfonic acid. The relative ease of acid-catalyzed hydrolysis [0.53 M H2SO4, H2O, PrOH (65 35), 20°] for compounds i, iii, acetonide, and ii is C5 C7 > acetonide C (e.g., t.//s for 1,2-O-alkylidene-a-D-glucopyranoses of C5, C7, acetonide, and C derivatives are 8, 10, 20, and 124 h, respectively). The efficiency of cleavage seems to be dependent upon the electronic environment about the ketal. ... 

The 2,2 -bis(phenylthiomethyl) dispiroketal (dispoke) derivative is cleaved by oxidation to the sulfone, followed by treatment with LiN(TMS)2. The related bromo and iodo derivatives are cleaved reductively with LDBB (lithium 4,4 -di- -butylbiphenylide) or by elimination with the P4- -butylphosphazene base and acid hydrolysis of the enol ether. The 2,2-diphenyl dispiroketal is cleaved with FeCl3 (CH2CI2, rt, overnight)." The dimethyl dispiroketal is cleaved with TFA, and the allyl derivative is cleaved by ozonolysis followed by elimination. ... 

In further modifications of these norprogestins, reaction of norethindrone with acetic anhydride in the presence of p-toluene-sulfonic acid, followed by hydrolysis of the first-formed enol acetate, affords norethindrone acetate (41). This in turn affords, on reaction with excess cyclopentanol in the presence of phosphorus pentoxide, the 3-cyclopentyl enol ether (42) the progestational component of Riglovic . Reduction of norethindrone affords the 3,17-diol. The 33-hydroxy compound is the desired product since reactions at 3 do not show nearly the stereoselectivity of those at 17 by virtue of the relative lack of stereo-directing proximate substituents, the formation of the desired isomer is engendered by use of a bulky reducing agent, lithium aluminum-tri-t-butoxide. Acetylation of the 33,173-diol iffords ethynodiol diacetate, one of the most potent oral proves tins (44). ... 

Although the preparation of /3-mercaptoethanesulfonicacid through the ammonolysis reaction is the preferred method, it is also possible to prepare the sulfonic acid by the sodium hydroxide hydrolysis of /3-S-thiuronium ethanesulfonate followed by the ion exchange treatment. The resulting acid, however, is generally not as satisfactory as that prepared by the am-monolysis reaction. 

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