Place 5.0 ml of 95% ethanol in a 10 ml Erlenmeyer falsk equipped with a stirrer bar. Put the flask in a sand bath, set atop a magentic stirring hot plate, and heat the ethanol to boiling. Immediately, with stirring, add 0.45 ml of salicylaldehyde. To the boiling solution, add 0.140 ml of ethylenediamine. Stir the solution for 4 minutes, and cool the solution in an ice-water bath. Collect the yellow crystals by suction. Wash the product with 2 drop of ethanol and dry on a clay tile. Determine the percentage yield.
Place 230 mg of salenH2 into a 25 ml two-necked flask equipped with a magentic stirring bar. Attach a pressure equalizing funnel, a water condenser fitted with a T-jpint for N2 flow, and an oil bubbler. Set the apparatus in a water bath on top of a magnetic stirring hot plate. Add 12 ml of 95% ethanol through the funnel. Stir the solution and flush with N2. Maintain a steady flow (1 bubble/s). Heat the water bath to 70-80 C.
Prepare a solution of 200 mg cobalt acetate tetrahydrate, in 1.5 ml water in a 10 ml beaker. Add this solution dropwise through the addition funnel to the salenH2 solution. At first a brown gelatinous precipitate will form. After 1 h of heating and stirring, the precipitate becomes bright red.
Discontinue the heat and N2 and immerse the flask in cold water. Filer the product crystals by suction. Wash the residue with a few drops of water, follwed by drop of 95% ethanol. Dry the product in a vacuum desiccator. Determine the % yield.
O2 adsorb - 50-100 mg Co(salen), 5 ml DMSO saturated with O2.
Experiment from Microscale Inorganic Chemistry, Szafran, Z.; Pike, R. M.; Singh, M.M. John Wiley and Sons, Inc.: New York, 1991.
© 2004 by Lawrence T. Sein. All rights reserved.
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