On the association and structure of radicals derived from dipyridil[3,2-a:2'3'-c]phenazine. Contrast between the electrochemical, radiolytic, and photochemical reduction processes.
The reduction of dipyridil[3,2-a:2'3'-c]phenazine, dppz, by pulse radiolytically generated e(-)(sol) or by the reaction of the dppz excited states with electron donors produces the radical dppzH(.). The dimer radical, (dppz)(2)H(.), exists in equilibrium with dppz with an association constant, K = 10(3) M(-1). The rate constant for the reaction of dppzH(.) with dppz is k = 4.3 x 10(6) M(-1) s(-1). DFT calculations on the structures of dppzH(.) and the doubly reduced and doubly protonated dppzH(2) rendered a planar structure for the former species and a bent one for the latter.
INIFTA-CONICET, Universidad Nacional de La Plata, C. C. 16, Suc. 4, 1900 La Plata, Argentina.
M P
MP
Juliarena
R O
RO
Lezna
M R
MR
Feliz
G T
GT
Ruiz
S
S
Thomas
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G
Ferraudi
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I
Carmichael