The Reactions of Formaldehyde with

This particular representation makes it easy to visualize formaldehyde as a step-growth monomer of functionality 2. Our principal interest is in the reactions of formaldehyde with the active hydrogens in phenol, urea, and melamine, compounds [II] [IV], respectively ... 

Manufacture, Processing, and Economic Aspects. Hydroxyacetic acid is produced commercially in the United States as an iatermediate by the reaction of formaldehyde with carbon monoxide and water. 

Other Nitrogen Compounds. The basis of the sophisticated nitrogen compounds Hsted in Table 10 is the reaction of formaldehyde with amino compounds. A significant amount of Hterature details investigation of the mechanism of action, particularly whether or not the antimicrobial activity depends on decomposition to formaldehyde (40—42). These compounds tend to have substantial water solubiUty and are more effective against bacteria than fungi and yeasts. Key markets for these compounds are metalworking fluids, cosmetics, and in-can preservation of paints (see Alkanolamines Amines, fatty amines). 

Manufacturing and Processing. Urea—formaldehyde fertilizers are prepared from the reaction of formaldehyde with excess urea (U/E mole ratio 1). The reaction proceeds in two steps. In Step 1, urea and formaldehyde are combined to form monomethylol [1000-82-4] and dimethylolurea [140-95-4] intermediates. 

The transition-state structure of the hetero-Diels-Alder reaction is generally found to be unsymmetrical. Houk et al. have for the reaction of formaldehyde with 1,3-butadiene calculated the C-C and C-0 bond lengths to be 2.133 A and 1.998 A, respectively, in the transition state using ab-initio calculations shown in Fig. 8.12 [25 bj. The reaction of formaldimine follows the same trend for the transition-state structure. 

Acid catalysts, such as metal oxides and sulfonic acids, generally catalyze condensation polymerizations. However, some condensation polymers form under alkaline conditions. For example, the reaction of formaldehyde with phenol under alkaline conditions produces methy-lolphenols, which further condense to a thermosetting polymer. 

Fraenkel-Conrat H, Brandon BA, Olcott HS. The reaction of formaldehyde with proteins. IV. Participation of indole groups. /. Biol. Chem. 1947 168 99-118. 

French D, Edsall JT.The reactions of formaldehyde with amino acids and proteins. Adv. Protein Chem. 1945 2 277-335. 

Fraenkel-Conrat H, Olcott H. The reaction of formaldehyde with proteins. V. Crosslinking between amino and primary amide or guanidyl groups. J. Am. Chem. Soc. 1948 70 2673-2684. 

Formaldehyde reacts with proteins to form adducts and cross-links.31516 Metz et al.3 have identified three types of chemical modifications after treatment of proteins with formaldehyde (a) methylol (hydroxymethyl) adducts, (b) Schiff bases, and (c) methylene bridges. The reaction of formaldehyde with proteins is summarized in Figure 19.1, but briefly, formaldehyde reacts primarily with lysine and cysteine to form methylol adducts. The methylol adduct can subsequently undergo a dehydration reaction to form a Schiff base. Adducted primary amine and thiol groups can undergo a second reaction with arginine,... 

Anticipated products from the reaction of formaldehyde with ozone or OH radicals in the atmosphere are carbon monoxide and carbon dioxide (Cupitt, 1980). Major products reported from the photooxidation of formaldehyde with nitrogen oxides are carbon monoxide, carbon dioxide, and hydrogen peroxide (Altshuller, 1983). 

Reductive methylation is achieved by the reaction of formaldehyde with ammonium chloride. It is carried out by heating the components at 100-120° and gives mono-, di- and trimethylamine in high yields (Eschweiler reaction) [312, 962]. No catalyst is needed part of the formaldehyde provides the necessary hydrogen while the other part is oxidized to formic acid. The same reaction can be applied to methylation of primary and secondary amines [962]. Reductive alkylation can also be accomplished by reducing mixtures of amines with acids which are first reduced to aldehydes (p. 171). 

This enzyme catalyzes the reaction of formaldehyde with xylulose 5-phosphate to produce dihydroxyacetone and glyceraldehyde 3-phosphate. 

A Mannich reaction is the reaction of formaldehyde with a primary or secondary amine and a compound with an active hydrogen atom. The product, an amine with a y-carbonyl, is called a Mannich base, useful in a number of synthesis reactions. An example is in Figure 15-23, and the mechanism is in Figure 15-24. 

The preparation of A-phenyl-substituted hydroxamic acids 125 in the reaction of formaldehyde with nitrosobenzene to give 124 is strongly catalyzed by Fe + ions, which stabilize the transition states 126 and 127 for the rate-controlling proton transfer from the carbon atom of nitrosocarbinolic cation intermediate 125 leading to the product 128 (Scheme 62) . 

Drumm, M. F. and J. R. LeBlanc, The Reactions of Formaldehyde with Phenols, Melamine, Aniline and Urea, Chap. 5 in Step-Growth Polymerizations, D. H. Solomon, ed., Marcel Dekker, New York, 1972. 

The reaction of formaldehyde with the meta positions of lignin clearly have considerable potential for the use of lignin, particularly heavily condensed alkali lignin, in polymeric applications. 

Urea itself is the starting material for the preparation of various important linear and cyclic urea derivatives. For example, the reaction of formaldehyde with urea leads to 1,3-dimethylolurea. Heating this product converts it into a polymeric methyleneurea resin of wide industrial importance in adhesives and coatings. 

Formaldehyde reacts with primary and secondary aliphatic amines but not with tertiary amines. The reactions with methyl and dimethyl amines proceed as follows HCHO + HaN. CH, - H. CH(OH). HN. CHS, HCHO + HN(CHj)a - HCH(OH). N(CHS)S The reaction of formaldehyde with... 

After receiving his Ph.D., Dr. French spent two years, 1942 to 1944, as a post-doctorate fellow in the laboratories of Professors J. D. Edsall and E. J. Cohn at Harvard Medical School. During this period, French worked in the area of amino acids and proteins, and he became especially interested in relating the structure of amino acids and proteins to chemical reactivity. With Dr. Edsall, he published an excellent review on the reactions of formaldehyde with amino acids and proteins. In this stage of his career, his interest was aroused in proteins that possess enzymic activity. In later years, much of his research was devoted to enzymes and their mode of action, and to the molecular mechanisms and theoretical aspects of enzyme action. 

Transition state structures (chair and twist-boat) for the reaction of formaldehyde with allylborane (255) and allylboronic acid have been located with ab initio calculations at the... 

Figure 5-51. The reaction of formaldehyde with the palladium(li) complex of the diphosphine gives a / -hydroxymethyl derivative. The same organic product is obtained from the reaction of the free ligand.

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