Phenylglyoxylic acid

The preparation of the 6-propyl to 6-undecyl derivatives, however, was performed by boiling for 30 min with potassium carbonate. Sodium methoxide in a mixture of ethanol and benzene was used for the cyclization of the thiosemicarbazone of phenylglyoxylic acid ester. ... 

A similar dependence of the stereoselectivity on the solvent and reaction temperature was found with the x-oxo amides 9 derived from phenylglyoxylic acid (R = C6H5) and 2-oxopropanoic acid (R = CH3) with amine F (Table 23)15. Thus, the highest selectivity was observed under chelation-controlled conditions in the presence of the Lewis acid titanium(IV) chloride. 

As well as the disubstituted C2-symmelrie pyrrolidines E and F, the monosubstituted (f> )-2-(mcthoxymethyl)pyrrolidine G can be used as chiral auxiliary for the diastereoselecti ve addition of organomctallic reagents to a-oxo amides16. As with the phenylglyoxylic acid derivatives derived from amines E and F. methyllithium or methylmagnesium bromide in diethyl ether preferentially attack the (,S)-mms-conformer 11 (R = ( 6H5), leading to predominant formation of the (2 S)-diastercomer by Re-side attack. 

Dimethyl-1,2-benzenediamine with phenylglyoxylic acid (PhCOC02H) gave 6,7-dimethyl-3-phenyl-2(17/)-quinoxalinone (212, R = Ph) (EtOH, reflux. 

Fig. 5.38 Reduction of 10-3m phenylglyoxylic acid at the mercury streaming electrode in acetate and phosphate buffers containing 1 m KN03 (1) pH 5.02, (2) pH 5.45, (3) pH 5.85, (4) pH 6.25. The curves 2, 3 and 4 are shifted by 0.2 V, 0.4 V and 0.6 V with respect to curve 1. The first wave is controlled by the surface protonation reaction while the second is a direct reduction of the acid anion. (According to J. Koryta)...

Scheme 33.10 Synthesis of substituted mandelic amides via enantioselective reduction of a phenylglyoxylic acid derivative.

The photoreactions of phenylglyoxylic acid (28) are similar to those of pyruvic acid. In isopropyl alcohol it is photoreduced to diphenyl tartaric... 

When Wistar rats were exposed to 50, 300 or 600 ppm [0.22, 1.30 and 2.60 g/m ] ethylbenzene intermittently for up to 16 weeks, the urinary recovery of metabolites increased with dose but not linearly. The metabolic pattern of ethylbenzene was affected by exposure level but not by the duration of administration. The amounts of 1-phenylethanol and -hydroxyacetophenone increased with increasing exposure, but those of phenylglyoxylic acid and hippuric acid decreased (Engstrdm et al, 1985). 

The stereochemical aspects of the fates of 1-phenyl-1,2-ethanediol and mandelic acid in rats have been examined by Drummond et al. (1990). The proportions of a dose of 1-phenyl-1,2-ethanediol converted to phenylglyoxylic and mandelic acids depend upon its stereochemistry. The i -diol is preferentially converted to i -mandelic acid (30% of the dose in 48 h) with 15% of the dose as phenylglyoxylic acid. In contrast, after administration of the 5 -diol, the major product is phenylglyoxylic acid (46% of the dose) with 16% as mandelic acid (JUS 80 20). 

Mandelic acid undergoes a chiral inversion, possibly by reversible oxidation to phenylglyoxylic acid. When -mandelic acid was administered, some 80% of the dose was recovered as phenylglyoxylic acid in 48 h with 16% as mandelic acid RJS 80 20). However, when racemic mandelic acid was given, 46% was excreted as phenylglyoxylic acid and 47% as i -mandelic acid. 

Inoue, O., Seiji, K., Kudo, S., Jin, C., Cai S.-X., Liu, S.-J., Watanabe, T., Nakatsuka, H. Ikeda, M. (1995) Urinary phenylglyoxylic acid excretion after exposure to ethylbenzene among solvent-exposed Chinese workers. Int. J. occup. environ. Health, 1, 1-8 Johnstone, R.A.W., Quan, P.M. Carmthers, W. (1962) Composition of cigarette smoke some low-boiling components. Nature, 195, 1267-1269 Jonsson, A., Persson, K.A. Grigoriadis, V (1985) Measurement of some low molecular-weight oxygenated aromatic and chlorinated hydrocarbons in ambient air and in vehicle emissions. Environ, int., 11, 383-392... 

Korn, M., Gfrorer, W., Herz, R., Wodarz, I. Wodarz, R. (1992) Stereometabolism of ethylbenzene in man gas chromatographic determination of urinary excreted mandelic acid enatiomers and phenylglyoxylic acid and their relation to the height of occupational exposure. Int. Arch, occup. environ. Health, 64, 75-78 Kostiainen, R. (1995) Volatile organic compounds in the indoor air of normal and sick houses. Atmos. Environ., 29, 693-702... 

Benzoylformic acid (phenylglyoxylic acid) [611-73-4] M 150.14, m 62-65°, 64.5-65.5°, 67°, b 84°/0.1mm, 163-167°/15mm. If the sample is oily then it may contain H2O. In this case dry in a vacuum desiccator over P2O5 or KOH until crisp. For further purification dissolve 5.5g in hot CCI4 (750ml), add charcoal (2g, this is necessary otherwise the acid may separate as an oil), filter, cool in ice-water until crystallisation is complete. Filter the acid, and the solvent on the crystals is removed by keeping the acid (4.5g) in a vacuum desiccator for 2 days. Slightly yellow crystals are obtained. It can be recrystd also from CeH /pet... 

Mesitylacetic acid has been prepared from 2,4,6-trimethyl-acetophenone by treatment with yellow ammonium sulfide and hydrolyzing the resulting amide with alkali,6 by the dry distillation of 2,4,6-trimethylmandelic acid,7 by heating 2,4,6-trimethyl-phenylglyoxylic acid with hydriodic acid and red phosphorus,8 and by treating mesitylacetonitrile with potassium hydroxide.4... 

AMOl CeHaftj phenylglyoxylic acid CeHsCOCOOH EtOH aq PO KOH 1 - - - - 0-2 -... 

Phenylglyoxal ic acid, AM01 Phenylglyoxyl ic acid, AM01 Phenylglyoxylic acid nitrile,... 

Deuterium isotope effects in the reactions of 2-nitroso-2-methyl propane with formaldehyde, glyoxylate, glyoxylic acid, pyruvic and phenylglyoxylic acid... 

Af-Phenylethanolamine, a300 Phenylethene, sll 77-Phenylformamide, f31 Phenylglyoxylic acid, b70 Phenylglyoxylonitrile, b68... 

---