Cobalt cage

Walker, G.W., Geue, R.J., Sargeson, A.M. and Behm, C.A. (2003) Surface-active cobalt cage complexes synthesis, surface chemistry, biological activity, and redox properties, J. Chem. Soc., Dalton Trans. 2992-3001. 

Geue R et al (1984) Metal-ion encapsulation cobalt cages derived from polyamines, formaldehyde, and nitromethane. J Am Chem Soc 106 5478-5488... 

The stereoselective reduction of spinach plastocyanin with several cobalt cage complexes (Scheme 26) has been reported, too [60]. These cage complexes are very useful for investigation of outer-sphere electron transfer reactions because of their inertness to hydrolysis and to loss of ligands in the redox reaction. 

A planar hexanuclear cobalt cage, [Co6 (PhSi02)6 2CKsolvent)6] , which has the same metal core as the manganese(II) cage 28, has been reported (87). The experimental details are so limited that it is difficult to identify the molecules attached in the axial positions of the six cobalt centers. 

A two-component system containing both the photosensitizer and the electron relay has been obtained by covalently linking a cobalt-cage subunit to an anthracene moiety. An. The system 27 is not fluorescent ( < 2 x 10 ), owing to the occurrence of an intramolecular quenching of the excited anthracene by the Co complex. Investigations on the photophysical features of 27 (i.e., transient absorp-... 

The synthesis of the cobalt cage complex with pendant pyridylmethyl arms (Scheme 41) was performed in excellent yield [111]. 

Two cobalt cage complexes with covalently linked anthracene chromophore (Scheme 124) have been studied as coupled photosensitizers (anthracene substituent) and electron relays (cage fragment) to produce hydrogen [305]. 

It was shown that the efficiency of energy transfer from the anthracene singlet excited state to the cobalt cage decreases with increasing length of the bridge. 

The high chemical stability of the cobalt cages allows the Co(III)/Co(II) redox states to be cycled repeatedly without decomposition. Besides, these compounds are soluble in water. Thus, Co(III) complexes with N3S3 donors can... 

X-ray molecular structure of cobalt cage 5.28 (reprinted with permission from reference ). 

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