Synthesis of an oxygen-carrying cobalt complex, Co(salen) = [N,N'-bis(salicylaldehyde) ethylenediimino]cobalt(II); [Salen]
(a) synthesis of Co(salen) complex: Co(OAc)2 •4H2O + salenH2 → Co(salen) + ?

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(b) determination of O2 uptake by Co(salen) and structure of Co(salen)-O2 adduct
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Minimum requirements: Characterization should involve at minimum: Cyclic voltammetry (for a). You should also determine the amount of O2 consumed in reaction (b). Test to see what happens upon exposing Co(salen)-O2 adduct to CHCl3.
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New methods: gas reactions, CV
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References to get you started:
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J. Chem. Soc. (A) 1969, 946.
Chem. Rev. 1984, 84, 137.
J. Chem. Educ. 1977, 54, 443.
J. Chem. Educ. 1989, 66, 854.
Inorg. Chem. 1981, 20, 1993.
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The following questions should be attached to the end of the report. These questions may also be asked during the prelab orals.
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Why can the Co(salen) be dried in air?

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Why is the brown form of Co(Salen) active toward oxygen and the red form inactive?

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What kind of solvents can be used for the O2 uptake experiment?

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Why does DMSO activate the red form of Co(salen)? Would addition of CHCl3 to the red form cause similar activation? Why?
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Why does the Co(salen) coordinate O2? (please provide the O2 MO diagram, Co oxidation state in Co(salen), d-orbital splitting diagram for Co(salen)).
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Formally, what can the reaction Co(salen) + O2 be regarded as?

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There are a couple of ways that O2, a diatomic molecule, can coordinate to a metal center. Draw and name the binding modes (coordination modes) of the diatomic gaseous molecule, O2, to the metal center in mononuclear TM complex? Keeping in mind these two binding modes, draw and name the possible binding modes of O2 to the metal centers of mononuclear TM complexes.
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How many moles of O2 does each Co(salen) molecule absorb? (draw a structure of the oxygenated product).

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Would N2, CO, H2, or NO react with Co(salen)? Why?
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