| Abstract: | Abstract Stereoselective electron-transfer between optically active Λ-Co(EDDS)]? and Co(diamine)3]2+ (diamine = racemic-1,2-diaminopropane (pn); R-1,2-diaminopropane (R-pn)) have been investigated in aqueous and in DMSO solutions. In aqueous solution, the reaction between Λ-Co(EEDS)]? and Co(pn)3]2+ produces four conformational isomers of the Co(pn)3]3+ complex which have the Λ-forms in excess. Their optical purities are increased ob3>lelob2> lel2ob> lel3 . In contrast, the reaction in DMSO results in more δ isomers than Λ and the sequence of optical purities are in reversed order. The reaction between Λ-Co(EDDS)]? and Co(R-pn)3]2+ in aqueous solution produces two conformational isomers of Co(R-pn)3]3+; their absolute configurations are identified as δ-lel2ob and Λ-ob3 . In DMSO, in contrast, the reaction produces only one isomer which is identified as δ-lel2ob. |
