Amines methylene chloride

The rate of stripping or the stripabiUty on cataly2ed urethane and epoxy resin finishes can be increased by adding formic acid, acetic acid, and phenol. Sodium hydroxide, potassium hydroxide, and trisodium phosphate [10101-89-0] may be added to the formula to increase the stripabiUty on enamel and latex paints. Other activators include oleic acid [112-80-17, trichloroacetic acid [76-85-9], ammonia, triethanolamine [102-71-6], and monoethyl amine. Methylene chloride-type removers are unique in their abiUty to accept cosolvents and activators that allow the solution to be neutral, alkaline, or acidic. This abihty gready expands the number of coatings that can be removed with methylene chloride removers. 

PMMA is not affected by most inorganic solutions, mineral oils, animal oils, low concentrations of alcohols paraffins, olefins, amines, alkyl monohahdes and ahphatic hydrocarbons and higher esters, ie, >10 carbon atoms. However, PMMA is attacked by lower esters, eg, ethyl acetate, isopropyl acetate aromatic hydrocarbons, eg, benzene, toluene, xylene phenols, eg, cresol, carboHc acid aryl hahdes, eg, chlorobenzene, bromobenzene ahphatic acids, eg, butyric acid, acetic acid alkyl polyhaHdes, eg, ethylene dichloride, methylene chloride high concentrations of alcohols, eg, methanol, ethanol 2-propanol and high concentrations of alkahes and oxidizing agents. 

Phosgene addition is continued until all the phenoHc groups are converted to carbonate functionahties. Some hydrolysis of phosgene to sodium carbonate occurs incidentally. When the reaction is complete, the methylene chloride solution of polymer is washed first with acid to remove residual base and amine, then with water. To complete the process, the aqueous sodium chloride stream can be reclaimed in a chlor-alkah plant, ultimately regenerating phosgene. Many variations of this polycarbonate process have been patented, including use of many different types of catalysts, continuous or semicontinuous processes, methods which rely on formation of bischloroformate oligomers followed by polycondensation, etc. 

Contaminants and by-products which are usually present in 2- and 4-aminophenol made by catalytic reduction can be reduced or even removed completely by a variety of procedures. These include treatment with 2-propanol (74), with aUphatic, cycloaUphatic, or aromatic ketones (75), with aromatic amines (76), with toluene or low mass alkyl acetates (77), or with phosphoric acid, hydroxyacetic acid, hydroxypropionic acid, or citric acid (78). In addition, purity may be enhanced by extraction with methylene chloride, chloroform (79), or nitrobenzene (80). 

Methylene chloride is one of the more stable of the chlorinated hydrocarbon solvents. Its initial thermal degradation temperature is 120°C in dry air (1). This temperature decreases as the moisture content increases. The reaction produces mainly HCl with trace amounts of phosgene. Decomposition under these conditions can be inhibited by the addition of small quantities (0.0001—1.0%) of phenoHc compounds, eg, phenol, hydroquinone, -cresol, resorcinol, thymol, and 1-naphthol (2). Stabilization may also be effected by the addition of small amounts of amines (3) or a mixture of nitromethane and 1,4-dioxane. The latter diminishes attack on aluminum and inhibits kon-catalyzed reactions of methylene chloride (4). The addition of small amounts of epoxides can also inhibit aluminum reactions catalyzed by iron (5). On prolonged contact with water, methylene chloride hydrolyzes very slowly, forming HCl as the primary product. On prolonged heating with water in a sealed vessel at 140—170°C, methylene chloride yields formaldehyde and hydrochloric acid as shown by the following equation (6). 

Eor use in paint strippers, one of its first appHcations, methylene chloride is blended with other chemical components to maximi2e its effectiveness against specific coatings. Typical additives include alcohols, acids, amines or ammonium hydroxide, detergents, and paraffin wax. Paint stripping formulations without methylene chloride have not as yet been shown to be as effective as those with methylene chloride. 

The reaction mixture was then dissolved in methylene chloride, the amine was removed by shaking with dilute hydrochloric acid, the reaction product was extracted from the organic phase by means of dilute sodium hydroxide solution and the alkaline solution was acidified with acetic acid to a pH value of 6. The 1 -hvdroxv-4-methyl-6-cvclohexvl-2-pyridone precipitated in crystalline form. It was filtered off with suction, washed with water and dried. The yield was 1.05 g (49% of theory) melting point 143°C. 

With Nitrogen Nucleophiles Aziridine-2-carboxylates react with primary and secondary amines, including anilines, to give a, 3-bisamino carboxylates [71, 113]. As an example, treatment of aziridine 153 (Scheme 3.55) with diethylamine in methylene chloride afforded compound 154 in 89% yield after chromatographic separation. 

NMe is now commercially available and is prepd by the vapor phase nitration of methane at a ratio of 9 moles of methane to I mole of nitric acid at 475° and a residence time of 0.18sec (Ref 12) or by the similar nitration of aliphatic hydrocarbons (Ref 8). Other prepns are from Me sulfate and Na nitrite (Ref 26) by the oxidn of Me amine with dinitrogen trioxide in the gas phase or in methylene chloride, yield 27%... 

An alternative method of synthesis of N3P3Cl6 has been developed recently, based on the reaction of tris (trimethylsilyl) amine and phosphorus pentachloride (40). This reaction either preferentially leads to the formation of N3P3C16 or to an N-silylated phosphoranimine intermediate C13P - NSiMe3, depending on the reaction conditions used. Thus the reaction between tris (trimethylsilylamine) and PC15 in methylene chloride at 40° C affords a mixture of cyclo and linear phosphazenes, which has been shown by an NMR analysis to contain up to 76% of N3P3C16 (Eq. 2). 

Organic solvents that can be used with discrete PEG compounds include DMSO, DMF, DMAC (i 7,N -dimcthylacetamide), and methylene chloride. The compounds also are very soluble in many other commonly used organic solvents, which provide flexibility for doing reactions. DMAC is particularly convenient, because it is easily dried of contaminating water (using molecular sieves), it doesn t decompose like DMF (producing amines), and it doesn t have the odors of some of the other solvents. Methylene chloride can be used for water-insoluble molecules that are to be reacted with the PEG compounds, but don t require subsequent water miscibility. 

A. l-Ethyl-3-(3-dimethylamino)propylcarbodiimide. A solution of 100 g. (1.41 moles) of ethyl isocyanate (Note 1) in 750 ml. of methylene chloride is prepared in a 5-1. three-necked flask equipped with a mechanical stirrer, an immersion thermometer, and a 500-ml., pressure-equalizing, addition funnel (Note 2). The flask and its contents are cooled to 5° in an ice bath, and a solution of 144 g. (1.41 moles) of N,N-dimethyl-l,3-propanedi-amine in 250 ml. of methylene chloride is added through the addition funnel at a rate such that the reaction temperature does not exceed 10° (Note 3). On completion of this addition 500 ml. of triethylamine is added to the flask, and a solution of 300 g. (1.6 moles) of -toluenesulfony 1 chloride in 300 ml. of methylene chloride is placed in the addition funnel and added to the reaction... 

ArgoGel-MB-CHO resin (366 mg, 0.42mmol/g substitution) was placed into an Ace pressure tube (note 5). Trimethyl orthoformate (TMOF 5 mL) was added to the flask along with the primary amine (10 equiv.). The tube was capped and heated for 2h at 70°C in a rotating oven (note 6), and cooled. The TMOF solution was removed with the use of a filtration cannula, and the entire process was repeated. The resin was washed with TMOF (5 mL, lx) and anhydrous methanol (5 mL, 3 x) Anhydrous methanol (5 mL) was added to the resin, followed by the addition of sodium borohydride (133 mg, 20 equiv.). After vigorous gas evolution had ceased, the tube was capped and agitated for 8 h at room temperature. The resin was then transferred to a polypropylene reaction vessel and washed with methanol (5mL, 3 x), methanol water (1 1, 5mL, 3 x), DMF water (1 1, 5mL, 3 x), DMF (5mL, 3 x), and methylene chloride (5 mL, 3 x). 

Direct phosgenation can also be carried out in aqueous sodium hydroxide rapidly stirred with methylene chloride containing a tertiary amine as catalyst. 

An elecrophilic Br+ or I+ can be successfully transferred to hydroquinidine (13) and two of its commercially available derivatives (4-chlorobenzoate and 9-phenanthryl ether hydroquinidines) simply by mixing two equivalents of the hydroquinidine with one equivalent of sym(co d ne)2-X+ perchlorate in methylene chloride or acetonitrile. H NMR studies (31) showed that the iodonium ion was associated with the nitrogen at the quinuclidine portion of the hydroquinidine instead of the aromatic nitrogen and also that all of the sym-collidines were removed from the X+ since only free collidine and no collidine-I+ peaks were observed. The (hydroquinidine)2-halonium ion is stable in solution for more than 30 minutes at room temperature these ions (and their parent amines) are more soluble in methylene chloride than in acetonitrile, and having R group other than hydrogen also improves the solubility. 

The reaction of AK6-amino-4-quinazolinyl)aminomethylenemalonate (1460, R = NH2) and acyl chloride in methylene chloride in the presence of pyridine at 0°C afforded the 6-acylamido derivatives (1505) (81EUP30156). When the amine (1460, R = NH2) was repeatedly reacted with acetic anhydride in pyridine, the /V,/V-diacetylamino derivative (1506) was obtained. Treatment of the amine (1460, R = NH2) with pivaloyl chloride in methylene chloride in the presence of pyridine gave the pivaloylamido derivative (1505, R = Me3C—), while in DMF in the presence of pyridine a mixture of the pivaloylamido and 6-formamido derivatives (1505, R = Me3C— and H) was obtained. 

Benzoylation of )V-(2,2-diethoxycarbonylvinyl)-/3-D-galactopyranosy-lamine and -/3-D-gluco analogue in pyridine with benzoyl chloride afforded mixtures of di-, tri-, and tetra-O-benzoyl derivatives. From 2,3,6-tri-O-benzoyl-N-(2,2-ethoxycarbonylvinyl)-j8-D-galatopyranosylamine and -/3-D-glucopyranosylamine the amines were liberated with bromine or chlorine in chloroform or methylene chloride (89MI4). 

Methyl 2,3-epoxypropanoate can be prepared by reaction of potassium glycidate with dimethyl sulfate and one equivalent of benzyltriethylammonium chloride in methylene chloride at room temperature (65% yield).14 The reactions of this ester with organolithium or organomagnesium reagents at low temperature afford optically pure epoxy ketones14 that may be transformed via reductive amination to anti amino epoxides.15... 

Irradiation at the DTBN-chloroform charge-transfer absorption yields151 285 ( = 1.01), 287 (4> = 0.6), terf-butyl chloride (4> = 0.06), isobutylene (tfi = 0.99) and di-terf-butyl (dichloromethoxy) amine 288 (4> = 0.56) (equation 131). Also151, irradiation of DTBN at 300 nm in methylene chloride gives 2-methyl-2-nitrosopropane and di-terf-butyl-terf-butoxyamine (

products characteristic of the locally excited (mi ) state, and also 2-methyl-2-nitrosopropane (

terf-butyl chloride (

terf-butyl (chloromethoxy) amine 289 (

charge-transfer state. 

Preparation of poly(m-phenylene)iso/terephthalate (80/20). The polymers were prepared by solution condensation of the acid chlorides with resorcinol in methylene chloride solution using triethyl amine as the acid acceptor as described by Korshak (10). 

N-NeoDentyl)-4-DihexylaminoDvrldinium Bromide (3h) The neopentyl salt was prepared in a similar manner from neopentyl mesylate, but reaction was carried out neat at 130 for 72 hr. Higher temperatures cannot be used, due to decomposition of neopentyl mesylate. The crude product was dissolved in water, basifled to neutralize any pyridinium salt, and was washed with petroleum ether to remove amine and unreacted neopentyl mesylate. The aqueous phase was acidified with HBr, and extracted with methylene chloride, to afford crude salt. Recrystallization from 20 1 ethyl acetate/acetonitrile affords the product (mp = 169-170 ). 

C. Crotyl diazoacetate. A solution of 10.0 g. (0.038 mole) of the />-toluenesulfonylhydrazone of glyoxylic acid chloride in 100 ml. of methylene chloride is cooled in an ice bath. Crotyl alcohol (2.80 g. or 0.038 mole) (Note 7) is added to this cold solution, and then a solution of 7.80 g. (0.077 mole) of redistilled triethyl-amine (b.p. 88.5-90.5°) in 25 ml. of methylene chloride is added to the cold reaction mixture dropwise and with stirring over a 20-minute period. During the addition a yellow color develops in the reaction mixture and some solid separates near the end of the addition period. The resulting mixture is stirred at 0° for 1 hour and then the solvent is removed at 25° under reduced pressure with a rotary evaporator. A solution of the residual dark orange liquid in approximately 200 ml. of benzene is thoroughly mixed with 100 g. of Florisil (Note 8) and then filtered. The residual Florisil, which has adsorbed the bulk of the dark colored by-products, is washed with two or three additional portions of benzene of such size that the total volume of the combined benzene filtrates is 400-500 ml. This yellow benzene solution of the diazoester is concentrated under reduced pressure at 25° with a rotary evaporator, and the residual yellow liquid is distilled under reduced pressure. (Caution This distillation should be conducted in a hood behind a safety shield) (Note 9). The diazo ester is collected as 2.20-2.94 g. (42-55%) of yellow liquid, b.p. 30-33° (0.15 mm.), n T) 1.4853 - 1.4856 (Note 10). 

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