The reaction of [Ru
6
C(CO)
16
]
2–
(
1
) with
NaOH in DMSO resulted in the formation of
a highly reduced [Ru
6
C(CO)
15
]
4–
(
2
), which was readily protonated by acids, such as
HBF
4
·Et
2
O, to [HRu
6
C(CO)
15
]
3–
(
3
). Oxidation of
2
with [Cp
2
Fe][PF
6
] or [C
7
H
7
][BF
4
] in CH
3
CN resulted in [Ru
6
C(CO)
15
(CH
3
CN)]
2–
(
5
), which was quantitatively converted into
1
after exposure to CO atmosphere. The reaction of
2
with
a mild methylating agent such as CH
3,
I afforded the purported
[Ru
6
C(CO)
14
(COCH
3
)]
3–
(
6
). By employing a stronger reagent, that is, CF
3
SO
3
CH
3
, a mixture of [HRu
6
C(CO)
16
]
−
(
4
), [H
3
Ru
6
C(CO)
15
]
−
(
7
), and [Ru
6
C(CO)
15
(CH
3
CNCH
3
)]
−
(
8
) was obtained. The molecular
structures of
2–5
,
7
, and
8
were determined by single-crystal X-ray diffraction as their [NEt
4
]
4
[
2
]·CH
3
CN, [NEt
4
]
3
[
3
], [NEt
4
][
4
], [NEt
4
]
2
[
5
], [NEt
4
][
7
], and [NEt
4
][
8
]·solv
salts. The carbyne–carbide cluster
6
was partially
characterized by IR spectroscopy and ESI-MS, and its structure was
computationally predicted using DFT methods. The redox behavior of
2
and
3
was investigated by electrochemical and
IR spectroelectrochemical methods. Computational studies were performed
in order to unravel structural and thermodynamic aspects of these
octahedral Ru–carbide carbonyl clusters...