Frit assembly

The high-pressure inlet is attached to a f in. cross to provide ports for gas introduction, pressure measurement, and thermocouple placement just in front of the frit. The Bourdon gauge (0-10 bar) should be connected via a tee to a purge valve to facilitate gas changes. Before use the assembly should be tested at 10 bar for leaks. Thermal insulation such as glass wool should be wrapped around the frit assembly to keep the expansion as adiabatic as possible. 

Plugged frit, pre-filter, guard column plugged inlet frit Backflush column/cartridge. Replace frit, pre-filter, guard column replace endfitting or frit assembly. 

Plugged frit in in-line filter or guard column plugged inlet frit Replace end-fitting or frit assembly. 

Figure 3. High vacuum line work station with solvent pot (left) and swivel frit assembly (right).

Adding Reagents to the Reaction Flask of the Swivel Frit Assembly... 

Condensable Gases. To add a desired quantity of a condensable gas, a a gas bulb of known volume is normally used. The working section, gas bulb and connection to the gas supply, manometer(16) and frit assembly are all evacuated (see Figure 1). If the frit assembly contains solvents or volatile materials, the lower flask is cooled to -78°C or -196°C before evacuation. The frit assembly... 

A sample of 83 (0.35 g, 0.94 mmol) and benzene (10 ml) were placed in a round-bottomed flask attached to a swivel-frit assembly. The soln was stirred under N2O (1 atm) at 55 °C for 3 d, after which the soln was filtered and the filtrate was taken to diyness under vacuum. The resulting solid was washed with petroleum ether (3x5 mL), and the blue product was collected on a filter frit to give microcrystalline 84 jdeld 0.16 g (44%). 

In a dinitrogen-filled glove box, 1 (0.420 g, 1.2 mmol) and ortAo-tolyllithium (0.18 g, 1.8 mmol) are transferred to a 50 mL round-bottomed flask fitted with a swivel frit assembly. The reaction mixture is stirred for 12 h at room temperature, and the volatile materials are removed under reduce pressure. Petroleum ether (10 mL) is transferred onto the solid in vacuum, and the resulting solution is filtered to remove LiCl. The residue is washed with additional pentane (2 X10 mL) using standard swivel frit techniques. The filtered washings are combined, concentrated to 3 mL, and cooled to —78°C. The resulting off-white precipitate is isolated by cold filtration. Yield 0.285 g (59%). 

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