Phenyl glyoxal

The reaction of these aldehydes, derived from periodate oxidation, with carbonyl reagents has also been investigated. Studies 147 148 were made on oxidized laminarin, a (1 —> 3)-linked polysaccharide, in which only the terminal residues had been oxidized. The addition of phenylhydrazine acetate detached the remainder of the terminal residue as glyoxal phenyl-osazone. When the aldehydic compounds derived from the periodate oxidation of raffinose and trehalose818a were reacted with p-nitrophenylhydrazine, the authors were surprised to find that one molecule of oxidized raffinose, containing six aldehydic functions, reacts with only three molecules of the reagent, and that the four aldehydic functions of the oxidized trehalose molecule react with only two. The reactions of periodate-oxidized carbo-... 

Glutaronitrile, 3-hydroxy-, 46, 48 Glycerol chlorohydrin, 46, 24 Glycine (-butyl ester, 45, 47 conversion to acetamidoacetone, 45,1 Glyoxal, phenyl-, 48,109 Glyoxals from esters and the potassium salt of dimethyl sulfoxide, 48, 112... 

Polyquinoxalines (PQ) have proven to be one of the better heat-resistant polymers with regard to both stabiUty and potential appHcation. The aromatic backbones are derived from the condensation of a tetramine with a bis-glyoxal, reactions first done in 1964 (61,62). In 1967, a soluble, phenylated version of this polymer was produced (63). The chemistry and technology of polyquinoxalines has been reviewed (64). 

Analog erhalt man aus 2-(4-Dimethylamino-phenyl)-glyoxal-diathylacetal 2-Hydr-oxy-2-(4-dimethylamino-phenyl)-acetaldehyd-diathylacetal2 (95% d.Th. Kp0>01 106°). In Methanol als Solvens werden u.a. folgende Alkohole erhalten ... 

Bei der Reduktion von 4-Brom- cy-diazo-acetophenon, die stufenweise bis zum 4-Brom-l-phenyl-athanol lauft, kann die Zwischenstufe 2-(4-Brom-phenyl)-glyoxal-hy-drazon bei der Reduktion in Mcllvaine-Pufferlosung an Quecksilber (—0,8 V) isoliert werden1 ... 

Benzenediamine (218) and the hydrochloride of ethyl 2-[A-cyclohexyl-(ethoxyformimidoyl)]glyoxalate [Et02CCOC(OEt)=N(CeHn)] (prepared in situ) gave A-cyclohexyl-3-oxo-3,4-dihydro-2-quinoxalinecarboxamide (222) (PhH-EtOH-CH2Cl, 40°C, 2 h 81% clearly needing an hydrolytic step). o-Anilinoaniline gave ethyl 3-oxo-4-phenyl-3,4-dihydro-2-quinoxalinecarboxy-... 

Methoxy-5,6-quinoxalinediamine (191) and glyoxal gave 5-methoxypyrazino [2,3-/]quinoxaline (192) (EtOH, H20, reflux, 1 h >70%) 195 2,3-di-phenyl-5,6-quinoxalinediamine and benzil likewise gave 2,3,8,9-tetraphenylpyra-zino[2,3-/]quinoxaline (193) (AcOH, reflux, 1 h %).955... 

A cross-coupling reaction of aldehydes with a-diketones proceeded in the presence of water to give the corresponding adducts in moderate to good yield. It is possible to use the substrates such as phenyl-glyoxal monohydrate, aqueous methylglyoxal, formalin, and aqueous a-chloroacetaldehyde for this reaction.330... 

The slow, rate-limiting step is almost certainly the migration of phenyl that occurs in the initial eOH adduct (135). This is essentially the analogue for 1,2-diketones of the intramolecular Cannizzaro reaction on the 1,2-dialdehyde glyoxal, OHCCHO (p. 217). In the latter... 

APG, p-azidophcnyl glyoxal, is a heterobifunctional crosslinker containing an arginine-specific diketone group on one end and a photosensitive phenyl azide group on the other end (Thermo... 

To corroborate the proposed mechanism, the catalytic reductive aldol coupling of acrolein with phenyl glyoxal monohydrate was performed under 1 atmos. elemental deuterium. Exposure of the aldol product to excess hydrazine in situ results in formation of the pyridazine, which incorporates precisely one deuterium atom in a manner consistent with the general mechanism proposed in Scheme 22.4 (Scheme 22.9). 

Scheme 22.9 Intermolecular reductive aldol coupling of acrolein and phenyl glyoxal under a D2 atmosphere.a)...

Scheme 22.13 Reductive coupling of 1-phenyl but-3-en-l-yne with phenyl glyoxal.

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