1.2- Dichloroethane phosgene

Acetaldehyde reacts with phosphoms pentachloride to produce 1,1-dichloroethane [75-34-3] and with hypochlorite and hypoiodite to yield chloroform [67-66-3] and iodoform [75-47-8], respectively. Phosgene [75-44-5] is produced by the reaction of carbon tetrachloride with acetaldehyde in the presence of anhydrous aluminum chloride (75). Chloroform reacts with acetaldehyde in the presence of potassium hydroxide and sodium amide to form l,l,l-trichloro-2-propanol [7789-89-1] (76). 

Fig. 6.11 Boiling temperature-composition diagrams for phosgene in (A) chlorobenzene [788], (B) 1,2,4-trichlorobenzene [788], (C) 1,2-dichloroethane (facing page) [1111], and (D) xylene (facing page) [1111].

Boiling temperature-composition curves for solutions of phosgene in chlorobenzene and 1,2,4-trichlorobenzene [788], and 1,2-dichloroethane and xylene (mixed isomers) [1111] are illustrated in Fig. 6.11(A)-6.11(D) for atmospheric pressure. 

In a flow system, at 200-250 C, phosgene combines with ethene over activated charcoal to give 1,2-dichloroethane, with an activation energy calculated to be 29.6 kj mol [1CI88,ICI89,ICI90]. A small quantity of chloroethene is formed at temperatures as low as 100 C from the simultaneous decarbonylation and dehydrochlorination of the intermediate acid chloride [ICI90] ... 

The photolysis of phosgene in the presence of ethene gives results which are quite different from those obtained by the photochlorination of ethene with molecular chlorine, in which the main reaction product is 1,2-dichloroethane. The proposed mechanism for the phosgene reaction is given below [2185] ... 

The gas phase reaction of phosgene with ethane-1,2-diol over activated charcoal results in the formation of 1,2-dichloroethane with a yield of about 70% at 210 C higher temperatures caused the decomposition of the diol [1C186]. 

Paraldehyde (2,4,6-trimethyl-l, 3,5-trioxane) was claimed to behave in a similar way [582], An early German patent, published after Eckenroth s note [582], claimed that no reaction occurs between COClj and aldehydes at normal temperatures [612], and attempts to repeat Eckenroth s preparation [582] have not been successful [1763]. However, by combining the vapours of phosgene and ethanal at atmospheric pressure in a flow system over an activated charcoal catalyst, 1,1 -dichloroethane and carbon dioxide are found to be co-produced, especially in the temperature range of 150-200 "C [1753,ICI98,ICI99]. It was confirmed that no reaction occurs in the absence of a catalyst between 25 and 400 C [1763]. 

Reaction of thioureas with phosgene is usually performed at room temperature in an inert solvent (such as benzene, chlorobenzene or 1,2-dichloroethane) in which the thiourea is soluble. By-products, if formed, are readily separated with ethoxyethane in which the chloroformamidinium chloride salts are insoluble. 

Depending upon the reaction conditions, ethanal can combine with phosgene to produce 1,1-dichloroethane, chloroethene, vinyl chloroformate or 1-chloroethyl chloroformate (see Section 10.3.3.1). However, imder conditions which produce 1,1-dichloroethane from phosgene and ethanal (charcoal catalyst, 150 C), carbonyl difluoride reacts (using a charcoal catalyst impregnated with caesium fluoride) to produce a mixture of the saturated 1 -fluoroethyl fluoroformate and the unsaturated vinyl fluoroformate (see Section 13.14.6.3.1). Thus, the COFj/CHjCHO/charcoal system is unstable with respect to dehydrofluorination, whilst the COClj/CHjCHO/charcoal system is unstable with respect to decarboxylation ... 

The reaction is accompanied by disproportionation (see Section 16.1.8.2), and as a result both 1,1-dichloroethane and CH3CHC10C(0)C1, were detected from the further reactions of the phosgene with ethanal [ICI117]. The same reactions occur, but to a much lesser degree, when carried out in an empty tube or in the presence of a silica catalyst [ICI117]. 

Desulfurization of petroleum feedstock (FBR), catalytic cracking (MBR or FI BR), hydrodewaxing (FBR), steam reforming of methane or naphtha (FBR), water-gas shift (CO conversion) reaction (FBR-A), ammonia synthesis (FBR-A), methanol from synthesis gas (FBR), oxidation of sulfur dioxide (FBR-A), isomerization of xylenes (FBR-A), catalytic reforming of naphtha (FBR-A), reduction of nitrobenzene to aniline (FBR), butadiene from n-butanes (FBR-A), ethylbenzene by alkylation of benzene (FBR), dehydrogenation of ethylbenzene to styrene (FBR), methyl ethyl ketone from sec-butyl alcohol (by dehydrogenation) (FBR), formaldehyde from methanol (FBR), disproportionation of toluene (FBR-A), dehydration of ethanol (FBR-A), dimethylaniline from aniline and methanol (FBR), vinyl chloride from acetone (FBR), vinyl acetate from acetylene and acetic acid (FBR), phosgene from carbon monoxide (FBR), dichloroethane by oxichlorination of ethylene (FBR), oxidation of ethylene to ethylene oxide (FBR), oxidation of benzene to maleic anhydride (FBR), oxidation of toluene to benzaldehyde (FBR), phthalic anhydride from o-xylene (FBR), furane from butadiene (FBR), acrylonitrile by ammoxidation of propylene (FI BR)... 

A solution of phosgene (13 g, 0.13 mol) in 1,2-dichloroethane (100 mL) was added slowly with stirring and cooling to a solution of a-isobutyl-/ -(dimethylamino)acrylaldehyde (20 g, 0.129 mol) in dichloroethane (50 mL). When the CO, evolution had ceased, the solution was distilled under vacuum on a steam bath, and to the residue was added pyriinidine-2,4,6-triamine (16.26 g, 0.13 mol) and anhyd EtOII (250 mL). This mixture was heated under reflux on a steam bath for 18 h, made strongly basic with NaOH, and heated for 1 li more. It was then cooled, and the precipitated pyridopvrimidine base was filtered and recrystallized from 70 % aq EtOH, which was acidified with HCI. The pyridopyrimidine hydrochloride was isolated yield 16.3 g (50%). 

Synthetic rubbers Butadiene, butenes, pentane, pentadiene, acrolein, acrylonitrile, dichloroethane, methyl methacrylate, methanol, phosgene, chlorobenzene, caprolactam, cyclohexane -... 

The polyarylesterketones can be produced by means of interaction between bisphenylsulfide, dibenzo rane and bisphenyloxide with monomers of electrophylic nature (phosgene, terephthaloylchloride) or using homopolycondensation of 4-phenoxybenzoylchloride and 4-phenoxy-4-chlorcarbonyl-bisphenyl in the presence of dichloroethane at 25 °C [282-285], Aromatic polyesterketones form after the polycondensation of 4-phenoxybenzoylchloride with chloranhydrides of tere- and isophthalic acids, 4,4 -dicarboxybisphenyloxide in the environment of nitrobenzene, methylchloride and dichloroethane at temperatures from -70 till 40 °C during 16-26 h according Friedel-Crafts reaction. 

Brazhnikov and Sakodynskii determined the retention time of boron trichloride on various supports and stationary phases and compared its behaviour to that of boronalkyls, Zelyaev et al used a molybdenum glass column packed with poly (methylsiloxane) on Spherchrom 1 to separate in amounts down to O.lppm of various trace impurities in boron trichloride, such as chlorine, phosgene, silicon tetrachloride, chloroform, carbon tetrachloride and dichloroethane. They used a column temperature of 60°C with nitrogen as carrier gas and employed thermionic and flame ionization detectors,... 

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