Several novel diazadioxa ferrocenyl derivatives havebeen prepared along with their previously unknownelectroactive precursor[(C
5H
5)Fe(C
5H
4CH
2N(CH
3)(CH
2)
2OCH
2-)]
2(
2). Di-N,N'-protonated and -methylatedspecies [
2(H)
2][X]
2(
3a-
c) (X =CF
3SO
3, BF
4, PF
6)and[
2(Me)
2][CF
3SO
3]
2(
5), and N-H-N monoprotonatedspecies [
2H][X] (
4a-
c) havebeen isolated in high yield. The efficient syntheses of compounds[
2Na][PF
6] (
6),[
2Cu][CF
3SO
3](
7),[
2Ag][CF
3SO
3](
8), and [
2MCl
2] (M = Zn, Hg)(
9,
10) are reported. The crystalstructureof complex
7 has been determined by X-ray analysis at 180 K.Crystal data: monoclinic
P2
1/
c, with
a =11.511(2) Å,
b = 19.613(2) Å,
c =14.493(2) Å,
= 88.32(2)
,
V =3273.2(1) Å
3,
Z = 4;
R =0.034,
Rw = 0.039 for3379 observations and 407 variable parameters. The copper(I)atom, bound to the two O and two N atoms of theferrocenyl ligand, is in a very distorted tetrahedral geometry with alarge N(1)CuN(2) angle (163.1(2)
).Incyclic voltammetry,
4a-
c undergo twoquasi-reversible (Fe(II)/Fe(III)) redox processes at 0.1 Vs
-1. Electrochemical studies of
3a-
c,
5,
7,and
8 show that diprotonation and dialkylation of
2 or complexation of a Cu (Ag) saltinduces an anodic shift ranging from 240 to 110 mV. Chemicaloxidation of
2 (5 equiv of Ag(I)) producesthecation [
2(H)
2]
4+(
11). The quantitative two-step electrochemicaloxidation of
2 at controlled potential inCH
3CNalso leads to
11: an ECE mechanism, in which thediprotonated species plays a key role, is proposed.Mössbauerdata of
2,
3c,
6,
7,
8, and
11 are also presented.
