Cuprous chloride, catalyst with oxygen

Oxidation of Mixtures of Monomers. The method most likely to yield random copolymers of DMP and DPP is the simultaneous oxidation of a mixture of the two phenols, although this procedure may present problems because of the great difference in reactivity of the two phenols. The production of high molecular weight homopolymer from DPP is reported to require both a very active catalyst, such as tetramethylbutane-diamine-cuprous bromide, and high temperature, conditions which favor carbon-carbon coupling and diphenoquinone formation (Reaction 2) from DMP (II). With the less active pyridine-cuprous chloride catalyst at 25 °C the rate of reaction of DMP, as measured by the rate of oxygen... 

Tn 1959 Hay (19) reported that 2,6-xylenol reacts with oxygen in the presence of a pyridine-cuprous chloride catalyst to yield a high molecular weight poly(l,4-arylene oxide) (Reaction 1). 

Derivation (1) From propylene oxygen and ammonia with either bismuth phosphomolybdate or a uranium-based compound as catalysts (2) addition of hydrogen cyanide to acetylene with cuprous chloride catalyst (3) dehydration of ethylene cyanohydrin. 

Sta.rting from Phenol. Phenol can be selectively oxidized into -benzoquinone with oxygen. The reaction is catalyzed by cuprous chloride. At low catalyst concentration, the principal drawback of this method is the high pressure of oxygen that is required, leading to difficult safety procedures. It appears that a high concentration of the catalyst (50% of Cu(I)—phenol) allows the reaction to proceed at atmospheric pressure (58). 

Into a bottle in an atmosphere of nitrogen was placed 0.2 g of cuprous chloride and several clean pieces of copper were added. To this was added 20 ml of pyridine. The mixture was agitated, forming a light brownish solution. The catalyst solution was very sensitive to oxygen. The solution was evaporated to dryness, leaving a complex of cuprous chloride with pyridine. 

The reactivity of each of the phenols in homopolymerization was determined by following the rate of oxygen absorption in a closed system. In each case, a plot of oxygen absorption against time was linear over at least 80 of the total reaction. Measurements were made at 25°C with a cuprous chloride-pyridine catalyst ai d at 60°C with a more active catalyst, cuprous bromide-tetramethylethylenediamine (TMEDA). Relative rates, from the slope of the linear portion of the oxygen absorption curves, are summarized in Table I. DMP is about 30 times more reactive than DDP at 25° C and five times more reactive at 60° C. MPP is intermediate in reactivity (as expected from its structure) at both temperatures but is comparable at the lower temperature with DMP and at 60°C with DPP (about a third slower than DMP at 25°C and 50 faster than DPP at 60°C). 

The catalyst solution is pumped from the flash drum to the bottom of another vertical cylindrical reactor. Air is compressed and enters the bottom of the reactor where it flows concurrently upward with the catalyst solution. Oxygen from the compressed air reacts with the catalyst solution at about 130°C (265 F) and 10 atm. (130 psig) to reoxidize cuprous chloride to cupric chloride. The exothermic heat of this reaction raises the temperature slightly and the reoxidized catalyst flows back to the ethylene oxidation... 

Catalyst for oxygenations (5, 165). Cuprous chloride or cuprous acetate can be used in catalytic amounts for oxygenation of various nitrogen compounds if it is first treated with oxygen to form a cupric salt. ... 

In the late 1950s processes for producing ethylene dichloride from ethylene by oxychlorination rather than by direct chlorination were developed. In these processes ethylene is treated with a mixture of oxygen and hydrogen chloride in the presence of a catalyst consisting of a mixture of cuprous and cupric chlorides ... 

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