Schlenk-type glassware

The syntheses of the precursors were carried out following procedures reported in the literature. All methods used distilled solvents, an argon filled glove box or Schlenk type glassware connected to a vacuum line. Thermoanalytical studies were carried out on a Setaram TG-DTA 92 analyzer in line with a Leybold Heraeus QX 2000 quadrupolar mass spectrometer. 

If a glove box is not available, Schlenk-type glassware used with medium vacuum and inert gas is a relatively inexpensive and convenient approach. The use of this glassware is described in a general reference.27 Dissolution, recrystallization, solution transfer, and other simple operations can be carried out on the benchtop. Syringe techniques using apparatus closed with rubber septa also have been developed.28... 

Previously reported syntheses of the title compound have involved vacuumline techniques.1-2 We describe here a procedure in which commercially available Schlenk-type glassware is used.j The synthesis involves the reaction of the protic hydrogen of trimethylammonium chloride with a hydridic hydrogen of [GaH4], to liberate hydrogen and form the desired amine gallium complex. 

This may be performed in Schlenk-type glassware of the type shown in Figure 3.4, consisting of a long tube with a side-arm and taps, both at this side-arm and the top ofthe flask. However, a round-bottomed flask (100 mL) fitted with similar taps is also effective. The side-arm is fitted with a rubber septum and the tap connecting this to the flask is closed. Under an atmosphere of argon, THF (ca. 25 mL) is distilled into the flask and the stopper closed. 

Caution. The syntheses described below should be carried out in a well-ventilated hood because of the release of CO and the strong stench of mercap-tides. Schlenk-type glassware should be used for most procedures. 

Ni(cod)2 is an air-sensitive complex requiring some care in handling. The yellow crystalline material (used as purchased, without further purification) is transferred in a glovebag under N, or in Schlenk-type glassware. Preparation of a stock solution of Ni(cod)2 (ca. 0.1 M in toluene) is convenient for small-scale reactions. This yellow solution can be stored in a freezer for at least 2 months with only slight deposition of a black precipitate. 

Conventional Schlenk-type glassware is used in the procedures described below and unless otherwise stated, all manipulations are carried out under nitrogen. All solvents are anhydrous and are freshly distilled under nitrogen prior to use. Solutions are stirred with a magnetic stirrer bar unless otherwise stated. 

Under appropriate conditions, column chromatography can be performed on air-sensitive organometallic compounds. Cannula transfer techniques allow chromatography to be done on the more stable compounds without the need for custom-made glassware. For these cases, a standard column is packed dry in the fume hood and then a septum and vent needle are attached. Degassed solvents are subsequently carmulated into the column and the adsorbent is packed tightly under a positive pressure of nitrogen. Eluted bands are then collected under Schlenk-type conditions. 

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