Synthesis and Characterization of a Cobalt-SALEN Oxygen Carrier

and Synthesis of an Epoxidation Catalyst

Last Update: September 2, 2005

The basic procedure of Szafran, Pike and Singh¹ will be used to prepare a cobalt complex that reversibly binds O₂.  You can use a different diamine and substituted salicylaldehyde instead ethylenediamine and salicylaldehyde.  You should be aware, however, that some of the resulting ligands may be difficult to deprotonate (i. e., Na or NaH may be required).

The preparation of the epoxidation catalyst is the same as that for the oxygen carrier, but instead of using cobalt, the manganese or chromium complex is prepared instead.  As with the oxygen carrier, you have the option of using a different diamine and a different aldehyde.  You also have the option of studying the reaction of the resulting compounds with O₃.

We have the salicylaldehydes and diamines shown below available for these syntheses.

Salicylaldehyde	2-Hydroxy-3,4-t-butylbenzaldehyde	Ethylenediamine	Phenylenediamine

Reference

 1. Szafran, Z.; Pike, R. M. and Singh, M. M. Microscale Inorganic Chemistry: A Comprehensive Laboratory Experience: John Wiley and Sones; New York, 1991, Experiment 30.