Glyoxylic acid monohydrate

Dissolve 4 g glyoxylic acid monohydrate in 220 ml water and add with stirring to a solution of 10 g 4,5, or 6 methoxy-tryptamine-HCl in 80 ml water. Adjust pH to 4 with 10% KOH and stir five hours at room temperature. Filter and wash with water to get about 4.5 g precipitate. Melt to decarboxylate or to 4 g precipitate add 30 ml concentrated HCI and 100 ml water and heat at 65° one hour. Add water to dissolve the solid and add excess 10% KOH. Filter to get the title compound or analog. 

Glyoxylic acid monohydrate is available from Pierce Chemical Company. 

Ethoxy carbonyl-7-methyl-4-oxo-6,7,8,9-tetrahydro-4H-pyrido[l,2a]pyrimidine Palladium on carbon Glyoxylic acid monohydrate Hydrogen... 

Glyoxylic acid monohydrate (1.96 g, 20 mrnoles) is dissolved in 200 ml of methanol, and a solution of 2.60 g (20 mmoles) of N-(2-hydroxyethyl) piperazine in 50 ml of methanol is slowly added thereto with stirring. 

Anhydrous tetracycline base (0.90 g, 2 mmoles) is dissolved in 30 ml of n-butanol at about 40°C. There is then added thereto under stirring a solution of 0.26 g (2 mmoles) of N-(2-hydroxyethyl)piperazine in 10 ml of butanol and 0.191 g (2 mmoles) of glyoxylic acid monohydrate. A precipitate appears after a few minutes and the suspension is maintained for six hours under stirring and at room temperature. 

Glyoxylic acid monohydrate 4-Hydroxy-3-methoxyacetophenone Ammonium Hydrazine hydrate... 

D.J. Bennett et al. developed a facile synthesis of A/-benzylallylglycine based on a tandem 2-aza-Cope/iminium ion solvolysis reaction. ° A/-Benzylallylglycine can be prepared in good yield through a one-pot reaction of N-benzylhomoallylamine with glyoxylic acid monohydrate in methanol. 

Petasis (borono-Mannich) condensation (Scheme 91) [353] To piperazinetrityl resin (32 mg, 0.030 mmol, loading 0.95 mmol g ) weighed out in a 10-mL Teflon fritted vessel was added a solution of glyoxylic acid monohydrate (0.032 mmol) in dry THE (2 mE). The suspension was allowed to mix under N2 at r. t. for 2 h. An excess of DEAM-PS boronic ester (120 mmol) was then added, followed by THP/EtOH 8 3 (v/v) (1.5 mE). The suspension was mixed under N2 at 55 °C for 48 h and then cooled at r.t. The resin mixture was filtered and washed as follows ... 

Aldol reactions. Aldol products are obtained in good yields from reaction of ketones with glyoxylic acid monohydrate with assistance of ultrasound irradiation. Substrate-control (by 1,3- + 1,5-asynmietric induction) of the aldol reaction involving y-amino-a-ketoesters under solvent-free conditions is very effective.- With lithium dicyclohexylamide and InCl, the reaction of esters with aldehydes furnishes P-hydroxy esters, and that of a-bromo esters affords a,p-epoxy esters." These are typical Reformatsky and Darzens reaction products, respectively. 

Preparation. The reagent is prepared in 71.8% yield by the reaction of benz-amide with glyoxylic acid monohydrate in refluxing acetone (5 hr.). 

An aq. soln. of glyoxylic acid monohydrate added dropwise during 4 hrs. at 0-5° to a stirred mixture of guaiacol and aq. NaOH, and stirring continued 20 hrs., while the temp, is allowed to rise to ca. 20° DL-4-hydroxy-3-methoxy-mandelic acid. Y 65-75%. A. J. Fatiadi and R. Schaffer, J. Research Nat. Bur. Standards 78A, 411 (1974). 

Loh and coworkers reported a one-pot Mannich-type reaction between aldehydes, aromatic amines, and silyl enol ethers in water in the presence of 20 mol% indium trichloride, giving the corresponding j8-aminoketones in 30-94% yields. - The use of glyoxylic acid monohydrate directly afforded the -amino adds. However, reactions using prochiral silyl enol ethers gave very low diastereoselectivities, the syn product being the major isomer. The catalyst could be recovered after completion of the reaction and reused for another reaction without any significant drop in activity. 

Glyoxylic acid monohydrate in ethanol stirred 30 min. at room temp, with morpholine, / -naphthol added, refluxed 1 hr., the solvent distilled off in vacuo, and the residue dissolved in 3 N HGl -> morpholino-(2-hydroxy-l-naphthyl)-acetic acid hydrochloride. Y 85-90%. F. e. s. E. Biekert and T. Funck, B. 97, 363 (1964). 

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