Aziridines reaction with carbonyl complexes

Cyclic Carhene Complexes. The reaction of aziridines with carbonyl, thiocarbonyl, or isonitrile ligands in Mn, Re, Fe, Ru, Pd, or Pt complexes leads to formation of cycHc carhene complexes (324—331). 

Rh-complexes in carbonylative ring expansion reactions of a variety of aziridines with carbon monoxide, which resulted in the formation of (3-lactams in good yields. It was reported that the catalytic system could be easily recovered by simple filtration and recycled without significant loss of activity. 

With the same concept, but using the more reactive Ti(III) cationic radical [Cp2TiCl(THF)2] or a cationic salphen aluminum complex in combination with the cobalt anion [Co(CO)4] , Coates et al. succeeded to make the epoxide or aziridine carbonylative ring expansion reaction catalytic (Scheme 60) [149]. For both substrates, it is proposed a nucleophilic attack of the cobalt anion at the least-substituted carbon atom of the three-membered ring, the latter being activated by the Lewis acidic part of the catalyst. Of note, catalysts 106 and 107 used in this reaction are described as ion pairs rather than M-Co bond containing complexes. 

A did not decrease as much as with poly(A) (50% from poly(A) and 60% for ssDNA). The decrease in area of peaks A and G can be explained in terms of the reaction of AZQ with purine residues. This reaction depletes the electroactive species available for the oxidation process at the GCE. The more pronounced decrease in peak area A implies that AZQ binds preferentially to adenine. The actual chemical structure of the AZQ-adenine is beyond the scope of this paper. However, a strong possibility is that there is a reaction between the N-7 of adenine and the aziridine group of AZQ. The stability of this complex is increased by hydrogen bonding of the carbonyl group of AZQ to the amino group of adenine. 

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