Meta-toluic acid

Beilstein Handbook Reference) AI3-15626 Benzoic acid, 3-methyl- BRN 0970526 EINECS 202-723-9 m-Methylbenzoic acid m-Toluic acid m-Toluylic acid meta-Toluic acid NSC 2214. Used in manufacture of N,N-diethyl-m-toluamide, a broad-spectnim insect repellent. Crystals mp = 108.7° bp = 263° d 2 = i.054slightly soluble in H2O, CHCI3. very soluble in EtOH, Et20 slightly soluble in H2O, soluble in organic solvents. CK Witco Chem. Cap. CK Witco Chem. Ltd. MitsubisN Gas. 

Meta Toluic Acid Ortho Toluic Acid Para Toluic Acid... 

Synthetic phenol capacity in the United States was reported to be ca 1.6 x 10 t/yr in 1989 (206), almost completely based on the cumene process (see Cumene Phenol). Some synthetic phenol [108-95-2] is made from toluene by a process developed by The Dow Chemical Company (2,299—301). Toluene [108-88-3] is oxidized to benzoic acid in a conventional LPO process. Liquid-phase oxidative decarboxylation with a copper-containing catalyst gives phenol in high yield (2,299—304). The phenoHc hydroxyl group is located ortho to the position previously occupied by the carboxyl group of benzoic acid (2,299,301,305). This provides a means to produce meta-substituted phenols otherwise difficult to make (2,306). VPOs for the oxidative decarboxylation of benzoic acid have also been reported (2,307—309). Although the mechanism appears to be similar to the LPO scheme (309), the VPO reaction is reported not to work for toluic acids (310). 

Oxidation of Xylene.—Just as toluene on oxidation has the methyl group converted into carboxyl yielding a mono-carboxyl or mono-basic acid, benzoic acid, so the xylenes by oxidation yield di-carboxyl or di-basic acids of the corresponding ortho, meta or para constitution. The two methyl groups are, moreover, possible of oxidation one at a time so that intermediate mono-carboxyl or mono-basic acids result in which one methyl group remains. The di-basic acids are known as phthalic acids and the mono-basic acids as toluic acids. 

The construction of a good scale of inductive constants, Oj, was successful the scale for the resonance constants presents many problems. The inductive scale was constructed from several molecular reference systems such as 4-substituted bicyclo [2.2.2]octane-l-carboxylic acids (65, 66, 67), a-substituted meta-and para-toluic acids (68, 69), and from comparison of base- and acid-catalysed hydrolysis of substituted acetates (43, 11) (i.e., the polar substituent constants a which is related to Oj). The aR scale can hence be obtained from equations 46 and 47. The precision of such determinations is inadequate because the factor a in equation 47 is too small. Values of aR were also obtained from NMR (70) and IR (71) measurements. The major problem with the oR scale is that the oR values are usually small with large standard deviations. Equation 48 is used to correlate rate or equilibrium constants with the double scale of [Pg.39]

In individual tests the meta- and para-toluic acids 37 and 38 were shown to be injurious to crops both pre- and postemergence. However, imidazolinthione 23 is selectively detoxified by cereals and is more effective in controlling selected weeds on cereals, especially postemergence (Figure 7). Unfortunately, 23 fails to control green foxtail and thus fails to provide a useful new range of activity on cereals. 

III. Structural Limitations - Few structural features have been reported which prevent dianion formation. Even benzoic acid can be metalated by proton abstraction17 ( eq l) or by metal-halogen exchange18 (eq 2). All three toluic acids form dianions, and dimethyl benzoic acids (eq 3) can be selectively metalated and alkylated.19 Ortho, meta and para methyl groups of dimethylbenzoic acids react in the order o>p>m. 

Toluic Acids, CH3.C6H4.COOH.—The three toluic acids can be prepared by the oxidation of the three xylenes with nitric acid, or from the toluidines, CH3.C6H4.NH2, by converting them by means of the diazo reaction into nitriles, which on hydrolysis are converted into toluic acids. The acids are crystalline substances, which are difficultly soluble in water. The ortho, meta, and para acids melt at 102°, 110°, and 180°, respectively. 

Aromatic Acids. The position and type of ring substitution in aromatic acids have a marked effect on the reaction rates and yields of amines. > p-Toluic acid yields 70% of p-toluidine,but from m-toluic acid only 24% of m-toluidine is obtained. If the time at which half of the total volume of nitrogen is evolved can be considered a measure of the reaction rate, the general conclusion can be drawn that in meta-substituted benzoic acids the reaction rates are in reverse order of the acidities as measured by dissociation constants. This generalization applies to the reaction rates but not to the yields of amines obtained from different meio-substituted benzoic acids. 

Toluic Acid, Meta 72.5 250 121 — - E - - plus 22 percent paratoluic acid. 2.6 orthotoluic acid. 2.6 benzoic acid. Alloy C -O. mpy... 

Toluene sulfochloride - 662 Toluene-isooctane mixture - 61 Toluene-kerosene mixture - 262 Toluenesulfonic acid - 38, 45, 51, 167, 178, 214, 373, 374, 377, 382, 404, 411, 718, 788 Toluenesulfonyl chloride - 770 Toluene vapor - 214 Toluic acid - 597, 788 Toluic acid, meta 718 Toluidines - 628 o-Tolyl chloride - 214 Tomato products (see Foods)... 

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