Stirrers Teflon

C. 4a(S),8a(R)-2-Benzoyl-1,3,4,4a,5,8a-hexahydro-6(2H)-isoquinolinone (3). A 1-L, three-necked, round-bottomed flask is equipped with a mechanical stirrer, Teflon-coated thermocouple, 500-mL addition funnel and a N2 inlet. Concentrated sulfuric... 

Hot-plate stirrer, Teflon-coated stirrer bar, and oil bath... 

Add carefully and slowly 15 cm cone, sulphuric acid to 25 cm of water stirred in a beaker cooled by iced water. Remove the coolant and add to the acid solution 6 g powdered boric acid and heat to dissolve it. Transfer to the fume cupboard and place on a hot plate/magnetic stirrer (Teflon-covered magnet). Add to the hot liquid, while stirring 15 g ammonium fluoride in small amounts (to avoid any loss of HF), continue heating below 100"C for half an hour. Allow to cool and then place in an ice/water bath to complete precipitation. When crystallisation seems complete, filter under suction. Dry by continued suction while pressing between filter paper. Transfer the crystalline product into a beaker containing 15 cm acetone. Shake well and refilter and finally weigh your product to the nearest eg and calculate the % yield based on ammonium fluoride. 

Stirrers are usually made of glass, but those of monel metal, stainless steel or Teflon (a polyfluoroethylene) also find application in the labora tory. An important advantage of a stirrer with a Teflon blade is that it is... 

Teflon stir bar 1 heavy duty balloon 1 roll of electrical tape Magnetic stirrer Support stand and clamps Ohaus triple beam scale 1 plastic funnel... 

The checkers used a stirrer for vacuum work (Teflon bearing, Fisher Scientific Company). The submitters used a mercury-sealed stirrer. 

The apparatus consists of a 1-1. three-necked flask equipped with a condenser, a dropping funnel, and a stirrer terminating in a stiff, crescent-shaped Teflon polytetrafluoroethylene paddle. The stirrer motor must have good torque (Note 1). The assembled apparatus, which is protected from moisture by means of drying tubes in the condenser and funnel, is preferably predried. About 216-224 g. (1.62-1.68 moles) of powdered anhydrous aluminum chloride is added to the apparatus with as little exposure to the moisture of the air as possible (Note 2). While... 

After drying under vacuum this iodo azide (2.43 g) is suspended in 50 ml of ether and added with stirring to a cold (0°) slurry of lithium aluminum hydride (1.2 g) in 70 ml of anhydrous ether in a 250 ml 3-necked flask (fitted with a reflux condenser and a mechanical stirrer with a Teflon blade). The remaining traces of the iodo azide are rinsed into the reaction flask with three 10 ml portions of ether. The reaction mixture is allowed to warm to room temperature and to stir for a total period of 11 hr. 

Stirrers with Teflon paddles should not be used. 

In a 250-ml. round-bottomed flask fitted with a glass-link or Teflon stirrer, thermometer, reflux condenser with outlet to an... 

A Thomas Magne-Matic Stirrer Model 15 (available from the Arthur H. Thomas Company, Philadelphia) was used in conjunction with a 5-cm., Teflon-coated, egg-shaped magnet. 

HPA catalyzed liquid phase nitration was eairied out in a Teflon-lined stainless autoclave of 200 mL equipped with a magnetic stirrer. Reactants and HPA were quantitatively added to the autoclave, which was sealed and heated in an oil-bath. Products were analyzed by GC with OV-101 30 m capillary column and FID detector by using calibrated area normalization and internal standard method. All products were confirmed by GC-MASS analysis. 

A significant advance was made in this field by Watarai and Freiser [58], who developed a high-speed automatic system for solvent extraction kinetic studies. The extraction vessel was a 200 mL Morton flask fitted with a high speed stirrer (0-20,000 rpm) and a teflon phase separator. The mass transport rates generated with this approach were considered to be sufficiently high to effectively outrun the kinetics of the chemical processes of interest. With the aid of the separator, the bulk organic phase was cleanly separated from a fine dispersion of the two phases in the flask, circulated through a spectrophotometric flow cell, and returned to the reaction vessel. 

---