Copper reaction vessel

Into an iron or copper reaction vessel having an efficient stirring device and furnished with a refluxing column and condenser, were charged 330 lb of high quality meta-cresol and 150 lb of glycerol, together with 25 lb of sodium acetate to serve as the catalyst in the reaction. 

The reaction vessel is situated inside a metal of high themial conductivity having a cylindrical, spherical, or other shape which serves as the calorimetric medium. Silver is the most suitable material because of its high themial conductivity, but copper is most frequently used. 

Storage vessels can be made in a large variety of shapes and sizes. Absorption and distillation towers are available in several different forms and many sizes. Reaction vessels such as coppers, stills and Cellarius receivers can be supplied in the special materials to withstand thermal shock. Valves and pumps of many types are available to suit all conditions. Piping can be... 

Thus nickel and nickel-copper alloy films evaporated in vacuo onto the inner walls of the reaction vessel have been chosen for further investigations. The films were deposited onto the inner wall of a glass tube kept at 450°C their thickness amounted to approximately 2000 A. After annealing at the same temperature in vacuo they were transferred into the side-arm of the Smith-Linnett apparatus in order for the recombination coefficients to be determined. The bulk homogeneity of alloy films prepared in this way was confirmed by X-ray diffraction (65, 65a, 66). 

The procedure described above provides a sufficient quantity of bis[copper(I) trifluoromethanesulfonate] benzene complex for several reactions at the scale used in Part C. If bis[copper(I) trifluoromethanesulfonate] benzene complex for a single reaction is desired, the same procedure can be followed at the appropriate scale without the use of the glove bag. In this case, the decolorized solution is not filtered but instead is cooled, and the product is allowed to crystallize in the reaction vessel. The supernatant benzene is decanted, and the crystals are washed in the flask with fresh benzene. The bis[copper(I) trifluoromethanesulfonate] benzene complex is then used without drying hj the same flask. 

Cul, 12mol% of 2,2 -dipyridyl, in lOvol of xylene diglyme (9 1) at 140°C with azeotropic removal of the water as it was formed. The azeotropic removal of water helped alleviate the problem of solids coating the reaction vessel walls, which led to stalling of the reaction. The reaction was complete in less than lOh, typically with 96% assay yield and 92% isolated yield for 49 after aqueous work-up and subsequent crystallization [14b-d]. It was noteworthy that this catalytic system composed of the copper(I) salt with bipyridyl ligand was recently reported to be applicable to a wide range of Ullmann-type ether formations [14d]. 

The use of metals or metallic compounds in microwave-assisted reactions can also lead to damage to the reaction vessels. As metals interact intensively with microwaves, the formation of extreme hot spots may occur, which might weaken the vessel surface due to the onset of melting processes. This will destroy the stability of the vessels and may cause explosive demolition of the reaction containers. If catalysts are used which can produce elemental metal precipitates (for example, of palladium or copper), stirring is recommended to avoid the deposition of thin metal layers on the inner surfaces of the reaction vessels. 

Figure 10 shows the instrumental setup used to implement the APP-CLS approach. It consists of (a) a CSTR that is a thermostated 10-mL glass reaction vessel accommodated in a commercially available spectrofluorimeter (a Hitachi F2000 model in this case) (b) a four-channel peristaltic pump with three channels used to dispense the reagent solutions and the fourth to keep the volume of the reaction mixture in the CSTR constant the three reagent solutions are as follows (1) 0.15 M hydrogen peroxide (2) 0.15 M sodium thiocyanate, 0.15 M sodium hydroxide, and 1.95 x 10 3 M luminol and (3) 6.0 x 10 4 M copper(II) sulfate ... 

There are several examples of the concerted mechanism. However, no report of an insertion of a carbon—carbon triple bond into a metallacyclopentadiene had appeared prior to discovery of this reaction. At low temperatures, during the reaction of zirconacyclopentadienes with DMAD, the formation of trienes (79) is observed upon hydrolysis. This clearly indicates that the benzene formation involves the insertion (addition) reaction of DMAD. As shown in Eq. 2.50, the alkenyl copper moiety adds to the carbon—carbon triple bond of DMAD and elimination of Cu metal leads to the benzene derivatives 72. Indeed, a copper mirror is observed on the wall of the reaction vessel. 

Zinc powder, obtainable from Mallinckrodt Chemical Works, St. Louis, Missouri, and Merck and Co., Rahway, New Jersey, is placed in a beaker and is washed consecutively and rapidly ( 10 seconds) with three 100-ml. portions of 3% hydrochloric acid, two 100-ml. portions of water, two 200-ml. portions of 2% aqueous copper sulfate (until blue color disappears), two 200-ml. portions of water, two 100-ml. portions of acetone, two 100-ml. portions of dimethylformamide, and is washed into the reaction vessel with dimethylformamide. This procedure is a modification of one described by Hennion and Sheehan.3... 

It prevented the adsorption of copper on the walls of reaction vessels which is a common problem with conventional methodology. 

The reaction itself is carried out in a 1-1. polyolefin bottle (Note 2) or fused silica flask (Note 3) fitted with an inlet tube (Note 4) leading to the bottom of the reaction vessel and a reflux condenser which is connected to a hydrogen chloride absorber or which leads directly to the hood. A condenser suitable for work with anhydrous hydrogen fluoride can easily be prepared from a glass-jacketed polyolefin, Teflon , silica, or copper tube (Note 5). 

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