Paraformaldehyde chloride

It is marketed as a 35-40 per cent, solution in water (formalin). The rpactions of formaldehyde are partly typical of aldehydes and partly peculiar to itself. By evaporating an aqueous solution paraformaldehyde or paraform (CHjO), an amorphous white solid is produced it is insoluble in most solvents. When formaldehyde is distilled from a 60 per cent, solution containing 2 per cent, of sulphuric acid, it pol5unerises to a crystalline trimeride, trioxane, which can be extracted with methylene chloride this is crystalline (m.p. 62°, b.p. 115°), readily soluble in water, alcohol and ether, and devoid of aldehydic properties ... 

When ammonium chloride is heated to a higher temperature (160°) with a large excess of anhydrous formaldehyde (as paraformaldehyde), trimethyl-amine hydrochloride (trimethylammonium chloride) may be obtained ... 

Mix 100 g. of ammonium chloride and 266 g. of paraformaldehyde in a 1-litre rovmd-bottomed flask fitted with a long reflux condenser containing a wide inner tube (ca. 2 cm. diameter) the last-named is to avoid clogging the condenser by paraformaldehyde which may sublime. Immerse the flask in an oil bath and gradually raise the temperature. The mixture at the bottom of the flask liquefies between 85° and 105° and a vigorous evolution of carbon dioxide commences at once remove the burner beneath the oil bath and if the reaction becomes too violent remove... 

The formaldehyde may be replaced by methylal CHjlOCH,), or by chloro-methyl ether CHjOCHjCl, produced from paraformaldehyde, hydrogen chloride and methyl alcohol ... 

Into a 1-litre three-necked flask, equipped with a reflux (double surface) condenser, a mechanical stirrer (preferably of the Hershberg type. Fig. II, 7, 8) and a gas lead-in tube extending to near the bottom of the flask, place 200 g. (227 ml.) of dry benzene, 20 g. of paraformaldehyde (1) and 20 g. of finely-pulverised, anhydrous zinc chloride. Support the flask on a water bath so arranged that the level of the water in it is about... 

Chloromethjlation Reactions. The introduction of the chloromethyl group to both aHphatic and aromatic compounds is carried out by reaction of paraformaldehyde [30525-89-4] and hydrogen chloride. This method is used for synthesizing methyl chloromethyl ether [107-30-2], benzyl chloride [100-44-7], and chloromethyl acetate. 

Alkylation involving formaldehyde in the presence of hydrogen chloride is known as chloromethylation (eq. 3). The reagent may be a mixture of formalin and hydrochloric acid, paraformaldehyde and hydrochloric acid, a chloromethyl ether, or a formal. Zinc chloride is commonly employed as a catalyst, although many other Lewis acids can be used. Chloromethylation of sahcyhc acids yields primarily the 5-substituted product 5-chlotomethylsahcyhc acid [10192-87-7] (4). 

The yield of the more active RRR-a-tocopherol can be improved by selective methylation of the other tocopherol isomers or by hydrogenation of a-tocotrienol (25,26). Methylation can be accompHshed by several processes, such as simultaneous halo alkylation and reduction with an aldehyde and a hydrogen haUde in the presence of staimous chloride (27), amino alkylation with ammonia or amines and an aldehyde such as paraformaldehyde followed by catalytic reduction (28), or via formylation with formaldehyde followed by catalytic reduction (29). 

Cellulose dissolved in suitable solvents, however, can be acetylated in a totally homogeneous manner, and several such methods have been suggested. Treatment in dimethyl sulfoxide (DMSO) with paraformaldehyde gives a soluble methylol derivative that reacts with glacial acetic acid, acetic anhydride, or acetyl chloride to form the acetate (63). The maximum degree of substitution obtained by this method is 2.0 some oxidation also occurs. Similarly, cellulose can be acetylated in solution with dimethylacetamide—paraformaldehyde and dimethylformamide-paraformaldehyde with a potassium acetate catalyst (64) to provide an almost quantitative yield of hydroxymethylceUulose acetate. 

Cyanuric acid readily dissolves in aqueous formaldehyde forming tris(hydroxymethyl)isocyanurate [10471-40-6] (THMIC) which can be isolated by evaporation (11). THMIC in turn reacts with acetic anhydride to yield tris(acetoxymethyl)isocyanurate [54635-07-3], either thionyl chloride or phosphoms pentachloride to give tris(chloromethyl)isocyanurate [63579-00-0], and phenyl isocyanate in pyridine to yield tris(A/-phenylcarbamoxymethyl) isocyanurate [21253-39-4] in 87% yield (65). Reaction of CA with paraformaldehyde and 2,6-dicyclohexylphenol yields... 

Bischloromethyl ether has been prepared by saturation of formalin with dry hydrogen chloride by the reaction of paraformaldehyde with phosphorus trichloride or phosphorus oxychloride, by solution of paraformaldehyde in concentrated sulfuric acid and treatment with ammonium chloride or dry hydrogen chloride, and by suspension of paraformaldehyde in seventy or eighty percent sulfuric acid and treatment with chlorosulfonic acid. It is formed together with the asymmetrical isomer when methyl ether is chlorinated and when paraformaldehyde is treated with chlorosulfonic acid. The present method has been published. ... 

A mixture consisting of 13.5 g of 4-(4 -hydroxyanilino)-7-chloroquinoline hydrochloride dissolved In absolute ethanol is treated with a solution of 4.3B g of diethylamine and 1. B g of paraformaldehyde in 20 cc of absolute ethanol. The reaction mixture is heated under reflux for 16 hours, evaporated to one-half volume and the warm solution treated with an excess of hydrogen chloride dissolved in absolute ethanol. Acetone is added to the warm solution until it becomes turbid and then the solution is cooled. The crude dihydrochloride which separates is collected and purified by recrystallization from methanol MP 240°-242°C. 

Paraformaldehyde (7.5 g) (0.25 mol) and 18.3 g (0.25 mol) of diethylamine are mixed in 25 cc of alcohol and warmed until a clear solution Is obtained. The solution is cooled and mixed with 26.6 g (0.10 mol) of 3,3 -diallyl-4,4 -biphenol in 25 cc of alcohol. After standing several hours, the solution is warmed for one hour on the steam bath, allowing the alcohol to boil off. The residue is then taken up in ether and water, the ether layer separated and washed with 2% sodium hydroxide solution and finally with water. The washed ether solution is dried over solid potassium carbonate, and filtered. After acidifying with alcoholic hydrogen chloride, the ether is distilled off and the alcoholic residue diluted with an equal volume of acetone. The crystalline hydrochloride is filtered off, triturated with alcohol, diluted with several volumes of acetone, filtered and dried MP 209°-210°C. 

A biopolymer produced by a particular strain of bacteria is becoming widely used as a substitute for clay in low-solids muds. Since the polymer is attacked readily by bacteria, a bactericide such as paraformaldehyde or a chlorinated phenol also must be used with the biopolymer. The system has more stable properties than the extended bentonite system, because biopolymer exhibits good rheological properties in its own right, and has a better tolerance to salt and calcium. The system can be formulated to include salt, such as potassium chloride. Such a system, however, would then be classed as a nondispersed inhibitive fluid. 

Palladous chloride in preparation of hydrogenation catalyst, 46, 89 Paraformaldehyde, conversion to form aldoximc, 46,13 Pelargonyl fluoride 46, 6 1-Pentalenecaeboxylic acid, octa hydro-, 47,10... 

A mixture of Mg (0.163 g atom) and chloromethyltrimethylsilane (0.163 mol) in ether (90 ml) was heated gently (air-gun) to initiate reaction (once started, the reaction can be very exothermic, and it should be cooled occasionally to maintain a gentle reflux). When all the Mg had dissolved, paraformaldehyde (5g, 0.166mol of CH20) was added, and reflux was continued for a further 2.25 h. The cooled mixture was diluted with ether, and washed with saturated ammonium chloride solution. The aqueous layer was re-extracted with ether, and the combined ethereal extracts were dried and concentrated. Distillation gave 2-trimethylsilylethanol (0.156mol, 96%), b.p. 34-35°C/1 mmHg. 

A later study382 using paraformaldehyde and hydrogen chloride as the source of the chloromethyl moiety, reaction (189)... 

The reliability of this work has also been questioned by Brown and Nelson339, who could not get any reaction at all with benzene under the conditions quoted by Szmant and Dudek382. If the benzene value is in error it could account for the low selectivities that were observed. By using the competition technique with a deficiency of paraformaldehyde (but an excess of hydrogen chloride) they obtained a toluene benzene reactivity ratio of 112 and partial rate factors of / Me = 117, /mMc = 4.37, /pM = 430. 

As previously discussed, solvents that dissolve cellulose by derivatization may be employed for further functionahzation, e.g., esterification. Thus, cellulose has been dissolved in paraformaldehyde/DMSO and esterified, e.g., by acetic, butyric, and phthalic anhydride, as well as by unsaturated methacrylic and maleic anhydride, in the presence of pyridine, or an acetate catalyst. DS values from 0.2 to 2.0 were obtained, being higher, 2.5 for cellulose acetate. H and NMR spectroscopy have indicated that the hydroxyl group of the methy-lol chains are preferably esterified with the anhydrides. Treatment of celliflose with this solvent system, at 90 °C, with methylene diacetate or ethylene diacetate, in the presence of potassium acetate, led to cellulose acetate with a DS of 1.5. Interestingly, the reaction with acetyl chloride or activated acid is less convenient DMAc or DMF can be substituted for DMSO [215-219]. In another set of experiments, polymer with high o -celliflose content was esterified with trimethylacetic anhydride, 1,2,4-benzenetricarboylic anhydride, trimellitic anhydride, phthalic anhydride, and a pyridine catalyst. The esters were isolated after 8h of reaction at 80-100°C, or Ih at room temperature (trimellitic anhydride). These are versatile compounds with interesting elastomeric and thermoplastic properties, and can be cast as films and membranes [220]. 

Palladium catalyst, 59,160 Palladium(II) chloride, 59,161 Paraformaldehyde, 56,40 Pentachlorophenyllithium, 59, 72 frans-2,4-Pentadienoic acid, 59, 1 2,4-Pentadienoic acids, 59, 6... 

In a 3-1. round-bottomed flask equipped with a reflux condenser (Note 1) are placed 176 g. (1.60 moles) of diethylamine hydrochloride (Note 2), 68 g. (2.26 moles) of paraformaldehyde, 600 ml. (8.1 moles) of acetone, 80 ml. of methanol, and 0.2 ml. of concentrated hydrochloric acid. The mixture is heated for 12 hours at a moderate to vigorous rate of reflux (Note 3). The light-yellow solution, in which a small amount of gelatinous solid remains, is cooled, and a cold solution of 65 g. of sodium hydroxide in 300 ml. of water is added. The mixture is extracted with three 200-ml. portions of ether, the combined extracts are washed with two 150-ml. portions of saturated sodium chloride solution, and the washes are re-extracted with two 150-ml. portions of ether. 

Chloromethyl esters are obtained quite readily by the action of paraformaldehyde on the appropriate acid chloride in the presence of a small quantity of zinc chloride as catalyst.1 It therefore seemed worth while to try the action of paraformaldehyde on fluoroacetyl fluoride, but the only product which could be isolated was a low-melting solid which appeared from its reactions to be methylene bisfluoroacetate, CH2(0 CO CH2F)2. The compound was submitted for physiological tests, and it was shown that the l.d. 50 subcutaneous injection into mice was about 10 mg./kg. Subcutaneous injection into rats with doses of 2-5, 5 and 10 mg./kg. all killed 1/1. 

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