Glycolaldehyde reactions

Other aldehydes which have been used in the reaction are pro-panal, butanal, glycolaldehyde, 3-hydroxybutanal, and a number of phenylacetaldehydeand benzaldehyde derivatives. Whereas condensation of tryptophan with acetaldehyde takes place even at room temperature and pH 6.7, the reactions with chloral, chloroacetaldehyde, and crotonaldehyde fail entirely. 

The alkoxy radical OC2H4OH formed in the process either dissociates into CH20 and CH2OH, or reacts quickly with 02 to form glycolaldehyde (HOCH2CHO) and H02 H02 is also formed by the reactions of CHO and CH2OH with 02, and contributes as well to NO oxidation ... 

The addition of ethylene decreased notably the energy consumption for NO removal. Niessen [33] obtained energy costs of 61 eV/NO removed in the absence of ethylene and only 9.6 eV/NO removed when ethylene is present in the gas mixture. However, the NO concentration does not change much, as NO is mostly converted to NOz. The main reaction products obtained in the presence of ethylene are N02, glycolaldehyde (OC2H3OH), formaldehyde (CH20), and oxirane. 

Arthur L. Weber (1998), now working at the Seti Institute of the Ames Research Center at Moffett Field, reports the successful synthesis of amino acid thioesters from formose substrates (formaldehyde and glycolaldehyde) and ammonia synthesis of alanine and homoserine was possible when thiol catalysts were added to the reaction mixture. On the basis of his experimental results, Weber (1998) suggests the process shown in Fig. 7.10 to be a general prebiotic route to amino acid thioesters. 

The reaction with ethyl acetoacetate has been extended to glycolaldehyde, and to carbohydrates other than n-glucose, by employing different experimental conditions it is probably applicable to aldoses in general. With d-fructose, yields are lower, but two molar proportions of water are liberated and a crystalline product results. This has a constitution similar to that of II but with the D-omhfno-tetrahydroxybutyl chain at the /3-position on the furan ring. The reaction has been applied successfully to other ketoses and... 

Glycolaldehyde is formed by heating 2 g. of dihydroxymaleic acid in 10 ml. of water until the evolution of carbon dioxide ceases. To the resultant solution is added 2 ml. of ethyl acetoacetate followed by 2 ml. of ethyl alcohol and 1 g. of zinc chloride. The mixture is heated for one hour on a steam bath, and the reaction mixture is extracted with benzene. The benzene extract is washed with a concentrated solution of sodium bisulfite, and evaporated, affording an oil which is saponified by heating with sodium hydroxide solution (10%) on a steam bath for one hour. It is then acidified with dilute hydrochloric acid and extracted with ether. The ethereal extract is dried with anhydrous sodium sulfate and the solvent is evaporated the residue crystallizes from ether m. p., 99°. 

D-erythro-Pentulose 5-phosphate (XLIV) has been formed by the action of transketolase on hydroxypyruvate (XLII) and D-glycerose 3-phosphate, the hydroxypyruvate being decarboxylated196 to active glycolaldehyde which then reacts with the triose phosphate by an acyloin reaction.28 The active glycolaldehyde is also formed from L-glycero-tetrulose, d-altro-heptulose 7-phosphate, D-fructose 6-phosphate, and D-i/ireo-pentulose 5-phosphate and it reacts with various aldehydes (acceptors) to give ketoses.198, 200 Thus, substitution of L-gfh/cero-tetrulose for hydroxypyruvate in the above experiment also resulted in formation of D-en/i/iro-pentulose... 

The tetrose phosphate (LVI) acts as an acceptor for active glycolaldehyde derived from n-i/ireo-pentulose 5-phosphate (LII), and thus, in the presence of transketolase, yields D-fructose 6-phosphate (LV) and D-glyc-erose 3-phosphate. The reverse of this reaction has been observed.200 The... 

It has been suggested15 that apiose [3-(hydroxymethyl)-D-g cero-tetrose] (LVII), a branched-chain pentose,47 originates from the aldol reaction of dihydroxyacetone with glycolaldehyde. The origin of this and all other branched-chain sugars so far encountered in natural products is uncertain, but they may arise from intermediate branched-chain carboxylic acids which are believed to be formed in the fixation of carbon dioxide (see above). 

The formation of a longer-chain product, glycerine triacetate, in Ru3(C0)12-acetic acid catalytic reactions can also be accounted for by Scheme 1. A glycolaldehyde ester intermediate would presumably be largely hydrogenated to a... 

A series of l/f-pyrrolo[2,l-r][l,4]oxazin-l-ones 196 are also the product of an LJgi multicomponent reaction between proline (and also other a-amino acids that gave the corresponding monocyclic compounds) and several isonitriles in the presence of commercially available glycolaldehyde dimer (Equation 3) <20010L4149>. 

Hydroformylation of formaldehyde to give glycolaldehyde is an attractive route from syn-gas toward ethylene glycol. The reaction is catalysed by rhodium arylphosphine complexes [39] but clearly phosphine decomposition is... 

The oxidation of glycolaldehyde by tetrachloroaurate was carried out in acetic acid-sodium acetate buffer and found to be first order in [Au(III)] and [glycolaldehyde]. H+ and Cr both retarded the reaction. A compatible mechanism was proposed, which involves a one-step, rate-determining, two-electron transfer and the involvement of three gold species, AuCH, AuClsCOHa), and AuClsCOH), the last being the most active. 

The oxidative behaviour of glycolaldehyde towards hexacyanoferrate(III) in alkaline media has been investigated and a mechanism proposed, which involves an intermediate alkoxide ion. Reactions of tetranitromethane with the luminol and luminol-peroxide radical anions have been shown to contribute substantially to the tetranitromethane reduction in luminol oxidation with hexacyanoferrate(III) in aerated aqueous alkali solutions. The retarding effect of crown ethers on the oxidation of triethylamine by hexacyanoferrate(III) ion has been noted. The influence of ionic strength on the rate constant of oxidation of ascorbic acid by hexacyanofer-rate(III) in acidic media has been investigated. The oxidations of CH2=CHX (where X = CN, CONH2, and C02 ) by alkaline hexacyanoferrate(III) to diols have been studied. ... 

Photolytic. Atkinson (1985) reported a rate constant of 2.59 x 10 " cmVmolecule-sec at 298 K. Based on an atmospheric OH concentration of 1.0 x 10 molecule/cm , the reported half-life of allyl alcohol is 0.35 d. The reaction of allyl alcohol results in the OH addition to the C=C bond (Grosjean, 1997). In a similar study, Orlando et al. (2001) studied the reaction of allyl alcohol with OH radicals at 298 K. Photolysis was conducted using a xenon-arc lamp within the range of 240-400 nm in synthetic air at 700 mmHg. A rate constant of 4.5 x 10 " cm /molecule-sec was reported. Products identified were formaldehyde, glycolaldehyde, and acrolein. 

Acharya SA and Manning JM (1983) Reaction of glycolaldehyde with proteins latent crosslinking potential of a-hydroxyaldehydes. Proc Natl Acad Sci USA 80, 3590-3594. 

Glomb MA and Monnier VM (1995) Mechanism of protein modification by glyoxal and glycolaldehyde, reactive intermediates of the Maillard reaction. J Biol Chem 270, 10017-10026. 

This thiamin pyrophosphate-dependent enzyme [EC 2.2.1.1], also known as glycolaldehyde transferase, catalyzes the reversible reaction of sedoheptulose 7-phos-phate with D-glyceraldehyde 3-phosphate to produce D-ribose 5-phosphate and o-xylulose 5-phosphate. The enzyme exhibits a wide specificity for both reactants. It also can catalyze the reaction of hydroxypyruvate with R—CHO to produce carbon dioxide and R—CH(OH)—C(=0)—CH2OH. Transketolase isolated from Alkaligenes faecalis shows high activity with D-erythrose as the acceptor substrate. 

Figure 7.4 Schemae of the formose reaction (a) spontaneous, slow formation of glycolaldehyde from formaldehyde (b) after one cycle, one new molecule of glycolaldehyde is produced. The structural isomers of sugars are specified by the carbon skeleton and by the position of the carbonyl group (open circle). (Adapted, with some modifications, from Maynard Smith and SzathmSry, 1995.)...

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