Reaction vessel with stirring and atmosphere controls

less steel pipes (approximately in. in diameter and 31/2 in. long) are fastened to the lid with threaded collars so that approximately 3 in. of pipe p...
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Charles Carraher, JI. Universitv of South Dakota

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Reaction Vessel with Stirringand Atmosphere Controls

I t is advantageous that many reactious be conducted in an irrert atmosphere with stirring. Examples of this are found in reaction systems where stirriug is required and oue of the reactants is oxygen- or water-sensitive. Examples include a t least some reactions in each of the following groups: (1) mono-, di-, and polyester production from water sensitive acid chlorides; (2) Friedel-Crafts reactions (such as the production of Zacetylfluorene from fluorene1); (3) reactive metal reactions such as sodium reactions to form sodium alkoxides; (4) Gatt,ermann-Iioch reactions (such as the preparation of p-phenyl benzaldehydeZ). We find the following reaction vessel quite satisfact,ory, inexpensive, and easily and readily assembled. (Blender, jar, and special fittings for screw cap including labor can be obtained for approximately $55.) Stirred reactions can be carried out using a Waring Blendor Model 1001, Series 724 or other stirriug motor, fitted wit,h a Kimax Emulsifying Mill Jar through which three 3/n-in. holes are drilled through the metal screw cap. Three staiuless steel pipes (approximately in. in diameter and 31/2 in. long) are fastened to the lid with threaded collars so that approximately 3 in. of pipe protrude through the top side of the cap. Before and during the reactiorr period, onc pipe is fitted with rubber tubing and connected to a nitrogen tank. A second pipe is fitted with a separatory funnel by use of a cork stopper which Schemrtic had two concentric holes drilled of the reaction V ~ S S ~ I . in it. One hole was drilled through

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Journal o f Chemical Education

the stopper to allow the funnel stem t,o protrude through the cork and into the pipe. A second hole (approximately in. in diameter) was drilled halfway through the cork stopper to allow the separatory fume1 and cork stopper to fit snugly on the pipe. The third pipe is connected to a piece' of rubber t,ubing leading to a trap for volatile liquids or gases. 111cases where nitrogen is not used, the nitrogen tube is plugged with a cork st,opper. Pre and post heating arrd cooliug can be effected by using the jar and fittiugs without the motor. The apparatus is usable in such reactions as rioted above and other reactions. To exemplify the use of the apparat,us let us cousider t,he stirred interfacial polymcrizatiorr of adipyl chloride in carbon tetrachloride with hydroquinoue in aqueous NaOH solutiou. Hydroquinoue in basic solutiorrs is oxygen sensitive. Hydroquinone is added to the reaction jar before the cap is screwed onto the reaction jar. The tubes of the cap are connected. Nitrogerr is passed through thc jar to flush out the oxygerr and allowed to run through the jar until the reaction is completed. Water, which has previously been boiled to drive out dissolved oxygetl and which corrtaius the appropriate amount of sodium hydroxide, is theu poured into the separatory fu~roel. The stopcock is opened and the aqueous solution allowed to run iuto the jar. The stopcock is closcd and the carbon tetrachloride solvent, which coutaius au appropriate amount of thc adipyl chloride, is poured into the separatory funnel. The bleuder is turned ou; the stopcock opened, allowing all the organic phase to eutcr the jar. After polymerieatiorr is complcte, weak acid is added to briug t,he pH of the aqueous phase to 0-7. The blender and rritrogen are turned off; the cap UIIscrewed, and the polymer recnvercd from the renctiou vessel. 'HoILNING,

' AD.\MS,R .

E. C., (Edilo).), Organic Sl,nlhesk, 3, 23 (I!)>>). (Eddor), Organic /