Carbonyl chloride isocyanate

Iminophosphoranes have also proved to be key intermediates because they react with carbonyl compounds, isocyanates, isothiocyanates, acid chlorides, carbon dioxide, and carbon disulfide to give a wide range of imines and heterocumulenes, which are intermediates to pteridines. The preparation of iminophosphoranes has been investigated... 

Primary amines react with phosgene (carbonyl chloride) to give isocyanates [38] faster than ureas at temperatures below about 100°C. For example, aniline reacts with phosgene to give phenyl isocyanate below 100°C, but carbani-lide is produced when the reaction mixture is warmed at 140°C unless excess phosgene is used [39]. 

The in situ generated disubstituted ureas (26) also react with phosgene to yield thermally unstable allophanoyl chlorides (27) and chloroformamides (28) (75). As shown in Figure 5, the allophanoyl chlorides eliminate hydrogen chloride to form the isocyanate. The chloroformamides, however, yield chloroformamidine-A/-carbonyl chloride (29), which decomposes to yield both carbodiimides (30) and isocyanide dichlorides (31). The carbodiimides simply contribute to yield loss. The isocyanide dichlorides, although present in small amounts, are a contributor to chlorine-containing impurities which detrimentally affect product performance. 

The alkyl-, alky laryl- and diarylcarbodiimides are the diimides derived from carbon dioxide, however, no direct formation of carbodiimides from amines and carbon dioxide is known. Interestingly, carbodiimides can be obtained from amines and carbon dioxide via a switteri-onic titanium complex (see Section 2.2.8). The major starting materials for the synthesis of carbodiimides are isocyanates, 1,3-disubstituted ureas or 1,3-disubstituted thioureas. The synthesis of isocyanates requires the use of the toxic carbonyl chloride or its oligomers. A book on the synthesis and reactions of isocyanates appeared in 1996. ... 

Aminocyclopropanes were easily acylated by acid chlorides, isocyanates or isothiocyanates (e.g. Refs 3, 24, 27, 36, 71, 80, 82, 125, 178, 179, 184, 224). Polyureas, polyurethanes or polyamides have been prepared from 1,2-diaminocyclopropane Reduction of the carbonyl group in 423 by lithium aluminum hydride worked quite well for tertiary amides 5,473.495. longer reaction times effected a ring-opening in the case of a secondary amide (423, R = H) (LiAlH4 reduction of secondary... 

Five-membered cyciic ureas (2-imidazoiidinones) react with COCl j exclusiveiy at the nitrogen atom to form cyciic ailophanoyi chlorides, 2-imidazoiidinone-l-(carbonyl chloride). In the presence of a base, dehydrochlorination resuits in the production of isocyanates [2087a] ... 

General Remarks Phosgene, perhaps the most effective CWA of WWI, also has been called (1) carbonyl chloride (or dichloride), (2) Collongite, (3) D-Stoff, (4) chloroformyl chloride, and (5) CG (Ryan et al., 1996). Its CAS is 75-44-5. It is estimated that recent annual U.S. production demand is approximately 5400 million pounds. Its most important industrial use is in the production of isocyanates (R-N=C=0) (http / www.the-innovation-group.com). 

DIMETHYLAMINO CARBONYL CHLORIDE (79-44-7) Combustible liquid (flash point 155°F/68°C). Rapidly hydrolyzed in water to dimethylamine, cmbon dioxide, and hydrogen chloride. Violent reaction with strong oxidizers. Acid or acid fumes form toxic chloride fumes. Aqueous solution is incompatihle with sulfuric acid, alkalis, ammonia, aliphatic amines, alkanolamines, alkylene oxides, amides, epichlorohydrin, organic anhydrides, isocyanates, vinyl acetate. May increase the explosive sensitivity of nitromethane. Attacks austenitic stainless steels, causing pitting and stress corrosion. 

Phenyl Isocyanate. Isocyanatobenzene carbanil phenylearbimide. C7HsNO mol wt 119.12, C 70.58%, H 4.23%, N 11.76%, O 13.43%. CtHsN—C—O. Prepd by passing carbonyl chloride into a hot soln of aniline in toluene, saturated with HC1 Hardy, J. Chem. Soc. 1934, 20ll. 

Carbonyl azides are usually obtained from the hydrazides, although in principle they can also be prepared directly from the carbonyl chlorides and sodium azide. They are frequently used as intermediates for synthesis of isocyanates, urethanes, ureas, amines, etc., and are often used in such work without isolation. 

The action of hot alkali on salts of the acids 195 (R = tert-a kyl) yields the acids 197, whereas nitrous acid at 0-5 °C yields the hydroxy acids 196. (l-Aminoalkyl)phosphonic diesters react with carbonyl chloride to give the corresponding isocyanates, which may be characterized as derived ureas or semicarbazides ... 

In the reaction of benzoyl isocyanate with phosphorus pentachloride reaction occurs exclusively on the C=0 group attached to the isocyanate moiety, and the chloroimidoyl-N-carbonyl chloride XXV is obtained in good yield ( ). 

We have recently observed that the reaction of carbamates with carbonyl chloride to yield isocyanates is catalyzed by DMF... 

Similar reactions occur on treatment of benzalaniline, carbodiimides, phenyl isocyanate and N-sulfinylaniline with iminium chlorides For example, from chlorodimethylformiminium chloride and phenyl isocyanate the 1 1 adduct CXXXVII is obtained, which on thermolysis (with elimination of carbonyl chloride) or hydrolysis yields the formamidine CXXXVIH... 

In the reaction of chloroformamidine-N-carbonyl chlorides LVI with arylamines a mixture of carbodiimides and isocyanates is obtained ( ). 

By analogy with the general synthesis of imidoyl chlorides it can be expected that carbamates and thiocarbamates undergo reaction with a variety of acid halides to afford 1-haloformimidates and 1-halothio-formimidates, respectively. For example, carbamates have been reacted with carbonyl chloride ( ), pyrocatecholphosphorus trichloride ( ), and phosphorus pentachloride ( ), and isocyanates were obtained. In view of the catalytic effect of N,N-dimethylformamide in the phosgenation of carbamates to isocyanates, the intermediacy of 1-chloroformimidates X is anticipated ( ). 

PEG-supported organic moieties 3. The PEG-bound amines 3 were then treated with various electrophiles such as benzoyl chloride, morpholine carbonyl-chloride, phenyl isocyanate, and sulfonyl chloride at ambient temperature to give corresponding acylated products. Treatment of the acylated products with 1 % KCN/methanol resulted in efficient cleavage from the polymer support to give corresponding products 4 in 99% yield with 84-94% HPLC crude purity (9). 

Acid Chloride to Isocyanate and Amine. mr-Isocyanatoazdbenzene and m-Aminoazobenzene from Azobmzene-mr-carbonyl Chloride, (Method of Naegeli and Tyabji with modifications. ) A solution of 0.7 g. of sodium azide in 2 cc. of water is added to a chilled solution of 2.45 g. of azobenzene-wi-carbonyl chloride in acetone (25 cc.) with swirling and cooling in an ice bath. The resulting suspension is diluted after about fifteen minutes with about 50 cc. of water to complete the separation of the azide, and the azide is filtered, washed with a little water, pressed as dry as possible, and dried in vacuum m.p. 76-77 weight, 2.2 g. 

Imines from a-halo carbonyls treated with oxalyl chloride are reported to give a-halo isocyanates, which upon careful hydrolysis cyclize to l,3-oxazetidin-2-ones. However, it is difficult to tell how general such a procedure might be since decarboxylation could compete with cyclization (Scheme 69) (80S571). 

On the pages which follow, general methods are illustrated for the synthesis of a wide variety of classes of organic compounds including acyl isocyanates (from amides and oxalyl chloride p. 16), epoxides (from reductive coupling of aromatic aldehydes by hexamethylphosphorous triamide p. 31), a-fluoro acids (from 1-alkenes p. 37), 0-lactams (from olefins and chlorosulfonyl isocyanate p. 51), 1 y3,5-triketones (from dianions of 1,3-diketones and esters p. 57), sulfinate esters (from disulfides, alcohols, and lead tetraacetate p. 62), carboxylic acids (from carbonylation of alcohols or olefins via carbonium-ion intermediates p. 72), sulfoxides (from sulfides and sodium periodate p. 78), carbazoles... 

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