Aluminium phosgene

The only reports of directed synthesis of coordination complexes in ionic liquids are from oxo-exchange chemistry. Exposure of chloroaluminate ionic liquids to water results in the formation of a variety of aluminium oxo- and hydroxo-contain-ing species [4]. Dissolution of metals more oxophilic than aluminium will generate metal oxohalide species. FFussey et al. have used phosgene (COCI2) to deoxochlori-nate [NbOa5] - (Scheme 6.1-1) [5]. 

Benzophenone has been prepared by the distillation of calcium benzoate,1 by the action of benzoyl chloride on benzene in the presence of aluminium chloride,2 by the action of phosgene on benzene in the presence of aluminium chloride,3 by the action of carbon tetrachloride on benzene in the presence of aluminium chloride followed by hydrolysis.4... 

The oxazolidinediones 94 are crystalline, stable solids that are a convenient source of dipeptides when heated in THF with amino adds. The compounds are prepared fiom N-protected amino adds and phosgene or triphosgene <99JOC2S32>. The diiral oxazolidinediones 95 act as Friedel-Crafts reagents with aromatic hydrocarbons and aluminium chloride, giving the ketones 96 in moderate yield but with high ee <99S423>. ... 

Chlorobromophosgene is formed by the action of aluminium bromide or boron bromide on phosgene at 140° C. ... 

The reaction of phosgene with dimethylaniline when carried out in the presence of aluminium trichloride or zinc chloride gives Crystal Violet,... 

In presence of aluminium trichloride, phosgene reacts with ethylene dissolved in carbon disulphide, forming -chloro-propionic chloride as well as polymerisation products of ethylene. By the action of phosgene on ethylene glycol at ordinary temperatures, glycol carbonate is formed according to the equation ... 

Like phosgene, as in the decomposition by heat or in presence of aluminium chloride thus it reacts with dimethylaniline forming Crystal Violet. ... 

Ferric chloride and anhydrous aluminium chloride decompose chloromethyl chloroformate even in the cold, while on heating to about 70° C. the reaction is more rapid, phosgene being formed. 

HM-MOR was dealuminated with phosgene between 673 and 973 K. Chemical analysis of samples combined with A1 NMR and Si NMR data allowed us to quantify the Si/Al ratio, the concentration of extra-framework aluminium and framework vacancies. The Si NMR spectra reveal progressive dealumination with increasing temperature, accompanied by formation of SiCl and Si(OH)2 defect groups. The former yields quantitatively SiOH groups. The result showed unambiguously that framework reconstruction occurred during dealumination. 

Phosgene proved to be an appropriate reactant to remove aluminium from the zeolite framework [1,2]. Detailed measurements have been carried out to investigate the adsorption of phosgene [3], the mechanism of dealumination by infrared spectroscopic and thermogravimetric methods [4], structural consequences [5], adsorption and catalytic properties of modified mordenites [6]. In addition an NMR study has been carried out, to measure the thermal stability of so-called hydroxy nests in H-mordenite dealuminated with phosgene [7]. 

MAS NMR data revealed that upon dealumination of mordenite with phosgene a part of the framework Al remains in the channels as octahedrally coordinated aluminium compounds. As a result of aluminium removal, framework vacancies and internal silanol groups are generated. The transformation of SiCl groups to SiOH groups is due to hydrolysis by ambient moisture. Framework reconstruction occurs during dealumination. 

Phosgene reacts, sometimes violently, with a large number of common inorganic (Chapter 9) and organic (Chapter 10) substances. Hazardous reactions with lithium, sodium, potassium, aluminium, lithium amide, hexa-2,4-diyn-l, 6-diol, propan-2-ol, and hexafluoropropene have been mentioned specifically [1787]. Mixtures of potassium and phosgene are reported to explode when subjected to shock [1913a]. In addition, phosgene... 

Phosgene, dichlorine and hydrogen chloride in waste-gases from the manufacture of aluminium chloride (also see Section 9.4.3) were completely removed by treatment with aqueous acidified iron(II) chloride solution in the presence of activated carbon [1571]. 

When phosgene is combined with A ,iV-dimethyianiiine in the presence of aluminium(III) chloride, Michler s ketone, 4,4 -bis(dimethylamino)benzophenone, is produced (see Section 10.2.1.1), which undergoes further reaction with lV,N-dimethylaniline (also in the presence of aluminium(ni) chloride or POCij) to give the colouring material "crystal violet", used in the production of methyl violet indicator paper. When Michler s ketone is warmed with Ai-phenyl-1-naphthylamine in the presence of POCI3, Victoria blue (4.13) is formed, which is used as a dye for natural fibres [718a]. 

Treatment of V-phenylaniline with COClj in the presence of aluminium(III) chloride gives diphenylamine blue, (4.14) [577]. Similarly, triphenylamine reacts with phosgene to form... 

Phosgene has many uses and potential uses as a synthetic intermediate. It reacts with aromatic compounds in the presence of aluminium(III) chloride to give mostly acid chlorides, although the passage of phosgene into benzene at 50 "C, in the presence of aluminium(III) chloride, produces benzophenone as the final product [1415a]. 4,4 -Diphenoxybenzophenone, (4.20), is prepared from diphenyl ether and phosgene under similar conditions it is used... 

Phosgene has been employed in the modification of the surfaces of cellulose-acetate membranes used for water desalination and waste water treatment [1450]. Similarly, phosgene has been used to surface-modify porous diaphragms for electrolytic cells [324]. Aluminium and aluminium-based alloys can be etched at a high rate when COClj is used in a mixed gas plasma [1004], as can semiconductors (see Section 9.12). 

Phosgene can be used as the starting material for the preparation of other potentially useful carbonyl halides and carbonyl pseudohalides. Reaction of phosgene with fluorspar, for example, gives COCIF (see Section 9.1.1 and Chapter 16). With aluminium(III) bromide, COBrj is formed (Section 9.1.2.6). Reaction of COClj with HF gives COFj (see Section 9.10.4 and Chapter 13), reaction with silver cyanide gives carbonyl dicyanide, CO(CN)j (Section 9.1.7), whereas reaction with a mixture of sodium fluoride and HCN gives the mixed carbonyl halide pseudohalide, COFCN (Section 9.1.7 and Chapter 13). The chemistry of these... 

A novel method for the preparation of phosgene is based on the observation that considerable amounts of COClj are evolved when aliphatic aldehydes - CH3CHO, MejCHCHO, or (CHjO)3 - react with CCl in the presence of aluminium(III) chloride [1005,1006]. The reaction of paraformaldehyde HO(CHjO) H n = 8-100 with CCI in... 

Phosgene has been formed at the graphite anode during the electrolysis of commercial calcium aluminates (for the production of aluminium-calcium alloys) when the aluminate content of the molten bath became low relative to the chloride-containing melt [233]. 

Various chlorinating agents combine with COj, COS, or CS to form phosgene. Carbon dioxide reacts directly with Clj over heated porcelain tubes filled with charcoal to give phosgene [1379]. Also, carbon dioxide is reported to react with PbCl at 700 C, or NiClj at 550 C, to produce small yields of phosgene [168] and the reaction of CO with heated aluminium(III) chloride has been patented [2158] as a process for the production of phosgene, based on the reaction ... 

In 1956, it was reported that heating equimolar quantities of phosgene and calcium fluoride at 500 C in a steel bomb gives CF (1%), CCIF3 (65%), CCl Fj (30%), CCI3F (5%), a trace of CCl, and some COFj and COCIF the formation of the fluoromethanes is promoted by the presence of aluminium(ni) fluoride, tin(IV) fluoride, iron(III) fluoride or antimony(V) chloride [1454] ... 

Aluminium(III) fluoride is insoluble in liquid phosgene, and does not appear to react with it, even upon heating under pressure [2128]. 

The interaction between phosgene and aluminium(lll) chloride is, perhaps, the most studied Lewis acid-base reaction of phosgene. Nevertheiess, the results of these studies are rather inconclusive. 

An extensive study of solutions of aluminium(in) chloride in liquid phosgene (in which it is extremely soluble) by Germann and coworkers [735-741,743,745,746] (which is discussed in more detail in Chapter 11) came to the overall conclusion that phosgene exhibits a seif-ionization, equation (9.1), and that 2AICI3.COCIJ, say, would best be described as [CO][Al2Clg]. These conclusions, even allowing for the more reasonable self-ionization... 

Huston s work [997] also indicated that the reaction between aluminium(III) chloride and COCIj resulted in the formation of the 1 1 adduct, AlCIg.COClj, which readily loses phosgene in vacuo at room temperature to yield pure aluminium(III) chloride. This was later confirmed independently by tensimetric titration (see Fig. 9.5) [376], and the i.r. spectrum (see Table 9.1) of the white product (m.pt. 25 C dissociation pressures of 4.8 kPa at 0 C and 58.66 kPa at 25 C) indicated that the phosgene was O-bonded, viz. [Cl2C=0—>A1C13], and that no [A1C1 ] was present [376]. From the data in this paper, the enthalpy of dissociation of the adduct can be calculated ... 

Examination of the i.r. spectra of solutions of aluminium(III) chloride with competing ligands has led to the following series of ligand strengths, with phosgene notably the weakest of those studied [1050] ... 

It has been reported that passing a mixture of carbon monoxide and dichlorine through a solution of aluminium(III) chloride in trichloromethane at 30-35 C results in the catalytic formation of phosgene [1628], Experiments in our own laboratories [1589b] show that there is no observable reaction in the dark, and that, in daylight, the presence of aluminium(lll) chloride solution had no detectable effect. 

Thus, over a period of eighty years, no single study of the COClj-AlClj system has agreed with any other clearly, a fresh examination of the problem is required. However, the interaction between aluminium(III) chloride and phosgene has formed the basis of two patents for the purification of aluminium(III) chloride by removal of iron(lll) chloride impurities, which apparently are not soluble in the COClj-AlClg system [174b,2199a]. 

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