Methylated acids

Inspect the paper in ultraviolet light—conveniently in front on a Hanovia ultraviolet strip light—in a dark room. The acids show up as intense blue fluorescent spots. Mark with a pencil the positions of all spots. The position of the two spots arising from solution (C) should be compared with the single spots arising from solutions (A) and (B). It is probable that the solution (B) of pure N-methylan-thranilic acid may also reveal a faint spot corresponding to anthranilic acid still present in minute traces in the methylated acid cf. p. 223). 

Indolizine, hydroxy-conformations, 4, 451 GLC retention times, 4, 451 synthesis, 4, 121 tautomerism, 4, 198, 452 Indolizine, 2-hydroxy-synthesis, 4, 463 Indolizine, 8-hydroxy-conformation, 4, 452 Indolizine, 2-hydroxymethyl-synthesis, 4, 461 Indolizine, 3-hydroxymethyl-synthesis, 4, 461 Indolizine, 6-hydroxymethyl-synthesis, 4, 461 Indolizine, methyl-mass spectra, 4, 187, 450 NM 4, 448 Indolizine, 2-methyl-diazo coupling, 4, 454 mass spectra, 2, 529, 4, 450 nitration, 4, 50, 454 nitrosation, 4, 454 reaction with diaryl disulfide, 4, 460 reaction with nitroethane, 4, 460 Indolizine, 3-methyl-basicity, 4, 454 Indolizine, 5-methyl-acidity, 4, 461 synthesis, 4, 466 Indolizine, 6-methyl-mass spectra, 4, 450 Indolizine, l-methyl-2-phenyl-nitration, 4, 454 nitrosation, 4, 454, 455 Indolizine, 3-methyl-2-phenyl-reaction... 

Pyrimidin-2( 1H )-one, l-methoxy-4,6-dimethyl-synthesis, 3, 112 Pyrimidin-2(lH)-one, 1-methyl-synthesis, 3, 112 Pyrimidin-2(lH)-one, 4-methyl-acidic p/fa, 3, 60 reactions, 3, 89... 

Enono (32) is synthesised from (34) which we discussed on page 366. After methylation, acid-catalysed opening of the three-memberod ring gives (35) in which the new methyl group (Me ) has equilibrated to the equatorial position by enolisation. 

In another recent study, the relative rates of hydrolysis of a series of orange N-methyl ] acid dyes of the 2-alkoxy-4-chloro-s-triazine type (7.10 R = methyl, ethyl or isopropyl)... 

Dyes in this hue sector are also derived from ] acid, N-methyl ] acid or y acid but the diazo component is usually a sulphonated 2- or 4-anisidine, as a methoxy substituent has a bathochromic influence. The highly substantive structure 7.94 is found in various haloheterocyclic (Z) dyes. As in the orange region, vinylsulphone dyes have the precursor grouping located on the diazo arylamine, as exemplified by structure 7.95. 

Methylpyridines are called picolines. 2-Picoline and 4-picoline may be deprotonated by treatment with a strong base, giving useful anions. The methyl acidity results because of resonance stabilization... 

Samples of both fulvic and humic acids were suspended in methanol and methylated with diazomethane. Both H and spectra of the free acids were obtained, at 299.94 MHz and 75.42 MHz respectively, on a Varian XL-300 spectrometer having a Nicolet TT-100 PET accessory. Spectra were obtained in D2O, in a 12-mm tube, with deuterated TSP (sodium 3-(trimethylsilyl)propionate-, , 3,3- 4) added as internal reference. GC/MS of methylated acids was conducted on a Hewlett-Packard Model No 5995 GC/MS/DA system equipped with a fused silica capillary column (12 m x. 020 mm ID, Hewlett Packard) internally coated with crosslinked methylene silicone. Infrared spectra were obtained with solid samples dispersed in KBr pellets, by using a Beckman IR-33 spectrophotometer. The various absorption peaks in IR and NMR were interpreted conventionally (9-10). 

The acid represented by the formula so modified no longer comes within the definition of the lactic series. It is carbo methylic acid, and difibrs essentially from glycoUic ncid and the lactic series in general, inasmuch as the carbon of its chlorous radical, oxat 0, is linked to the carbon of the basylous radical by oxygen. ... 

Non-oxidative hydrocarboxylation of alkenes to carboxylic acids with CO and H20 is catalyzed by palladium complexes such as PdCl2(PhCN)2 or PdCl2(PPh3)2, and a-methyl acids predominate in the presence of HC1.374,443 A recent improvement of this reaction consisted of the use of a PdCl2/CuCl2/HCl catalyst under oxidative conditions.377 Almost quantitative yields of a-methyl carboxylic acids and dicarboxylic acids were obtained from terminal alkenes and terminal dialkenes respectively, at room temperature and atmospheric pressure (equation 174).377... 

Percival and Thomson44 obtained a mixture of disaocharide esters from which, on hydrolysis and derivatization, they isolated 2,3,4,6-tetramethyl-D-galactose anilide and a mixture of methylated acids. From these acids they obtained 3,6-anhydro-2,5-dimethyl-L-galactonic acid, the structure of which was determined by almost the same means as those employed by Jones and Peat.23 On methanolysis of hexamethylagarobiose, Araki28 isolated 3,6-anhydro-2,5-dimethyl-L-galactose dimethyl acetal (XIII),... 

In the diazines, methyl acidity can also be utilized condensation of 3-methylpyridazine with substituted araldehydes in basic medium gives alkenes 668 <2005T10227>. 

Parallel analyses by IR, thin-layer chromatography (TLC), and gas chromatography-mass spectrometry (GC-MS) of organic remains adhering to shards of ancient amphoras excavated in the harbor of Carthage (Tunisia) identified these remains as pine pitches. Capillary GC of methylated acid fractions showed abietic acid, dehydroabietic acid, and 7-ketodehydroabietic acid as the principal components. Two-dimensional TLC of untreated ether extracts revealed abietic acid in 12 of 31 samples and dehydroabietic acid in 26 of 31 samples. IR spectra of solid, raw samples indicated the presence of isopropyl groups, characteristic of the abietane skeleton, in 80% of the samples. Rapid and convenient analysis by TLC and IR was, in most cases, sufficient to identify pine resin products even after extensive pyrolytic and oxidative degradation. 

Methylation of phenols and alcohols. Phenols and alcohols are converted into methyl ethers by treatment with sodium hydride methyl iodide in THF at room temperature. The reaction is even applicable to hindered phenols (2,6-di-t-butyl-/>-cresol, 86% yield) and alcohols (triphenylcarbinol, 85% yield). However, acidic phenols (p-nilrophenol) are not methylated by this procedure even at 80°. This behavior contrasts to that of diazomethane, which readily methylates acidic phenols. 

The preparation of this acid is carried out on the same lines as the arsenation of o-eresol (see preparation of the 8-methyl acid), the o-crcsol being replaced by i-cresol and the temperature of the mixture maintained at 140° to 146° C. for seven hours. From 720 grams of syrupy arsenic acid and 300 grams of wi-cresol, a yield of 138-8 grams of the arsinic acid is obtained in the fornr of its sodium, salt. The free acid is obtained from the sodium salt by the aid of hydrochloric acid. The arsinic acid crystallises from hot water in white needles, which gradual melt at 194° to 195° C. 

A trisaccharide isolated from milk was completely hydrolyzed by /3-galactosidase to galactose and glucose in a 2 1 ratio. Reduction of the original trisaccharide with NaBH<, followed by exhaustive methylation, acid hydrolysis, then another NaBH< reduction step, and finally acetylation with acetic anhydride yielded three products (a) 2,3,4,6-tetramethyl-1,5-diacetyl-galactitol, (b) 2,3,4-trimethyl-l,5,6-triacetylgalactitol, and (c) 1,2,3,5,6-... 

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