In the methylation of a primary amine * if there happens to be an OH reactive group in the aromatic amine (primary amino alcohol) will the methylation with oxalic acid and paraformaldehyde at 100 C or other methods, affect the OH group ..java
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ReferencesA SOLVENT-FREE AND FORMALIN-FREE ESCHWEILER-CLARKE METHYLATION FOR AMINESThomas Rosenau,1 Antje Potthast,1 Ju¨ rgen Ro¨ hrling,1 Andreas Hofinger,1 Herbert Sixta,2 and Paul Kosma1,SYNTHETIC COMMUNICATIONS, 32(3), 457–465 (2002)http://mihd.net/2rl6deAbstractPrimary and secondary amines are N-methylated by a mixture of paraformaldehyde and oxalic acid dihydrate in good to excellent yields. The reaction proceeds without involvement of organic solvents and toxic formalin. Reaction temperatures of 100 C are required for the decomposition of oxalic acid
into the intermediate formic acid which acts as the actual reductant. The reaction conditions have been optimized, and the mechanism has been elucidated by means of deuteration experiments.
other referencesThe Action of Formaldehyde on Amines and Amino Acids'BYH . T.C LARKEH, . B. GILLESPIAEN D S. 2. WEISSHAUSJournal of the American Chemical Society 0002-7863, vol: 55 1933 p:4571http://mihd.net/176lgcSummarySimple aliphatic amines are smoothly methylated to the corresponding tertiary amines by warming in formic acid solution with formaldehyde.Dibenzylamine, under these conditions, is mainly converted into methyldibenzylamine, but at the same time yields some benzaldehyde and a more volatile base (probably dimethylbenzylamine).
Tetra-alkyl-diaminomethanes,o n warming with formic acid, are converted into equimolar quantities of the corresponding dialkylamine and methyldialkylamine. Hexamethylenetetramine reacts with warm formic
acid yielding mainly ammonia and trimethylamine, with smaller amounts of mono- and dimethylamines; only three-quarters of the methylene carbon reappears as methyl in the final mixture.
Only about two-thirds of the anticipated amount of carbon dioxide, calculated on the assumption that the formic acid is the sole hydrogen donor, is obtained in these reactions; apparently some of the formaldehyde also contributes hydrogen.
Amino acids react with formaldehyde in warm formic or acetic acid with detachment of some of the nitrogen in the form of volatile bases. Dimethyl derivatives were isolated from the reaction in formic acid with glycine, P-aminopropionic acid, a-aminoisobutyric acid and a-amino-aphenylbutyric acid. Other amino acids yielded breakdown and condensation of various degrees of complexity. Benzaldehyde was
isolated from a-aminophenylacetic acid, propiophenone from a-amino-aphenylbutyric acid, and a-(4-phenyl-2,3-diketopyrrolidyl)-/3-phenylpropionic acid from phenylalanine. Mechanisms by which these products may be formed are suggested.