A novel double-open-cubane (NNCO)
6
Co
4
Cl
2
cluster with a Co
4
O
6
core was
made
available under aqua-ultrasonic open atmosphere conditions for the
first time. The ultrasonic clusterization of the (3,5-dimethyl-1
H
-pyrazol-1-yl)methanol (NNCOH) ligand with CoCl
2
·6H
2
O salts in ethanol yielded a high-purity and
high-yield cluster product. Energy-dispersive X-ray (EDX), Fourier
transform infrared (FT-IR), and ultraviolet (UV)–visible techniques
were used to elucidate the clusterization process. The double-open-Co
4
O
6
cubane structure of the (NNCO)
6
Co
4
Cl
2
cluster was solved by synchrotron single-crystal
X-ray diffraction (SXRD) and supported by density functional theory
(DFT) optimization and thermogravimetric/differential TG (TG/DTG)
measurements; moreover, the DFT structural parameters correlated with
the ones determined by SXRD. Molecular electrostatic potential (MEP),
Mulliken atomic charge/natural population analysis (MAC/NPA), highest
occupied molecular orbital/lowest unoccupied molecular orbital (HOMO/LUMO),
density of states (DOS), and GRD quantum analyses were computed at
the DFT/B3LYP/6-311G(d,p) theory level. The thermal behavior of the
cluster was characterized to support the formation of the Co
4
O
6
core as a stable final product. The catalytic property
of the (NNCO)
6
Co
4
Cl
2
cluster was
predestined for the oxidation process of 3,5-DTBC diol (3,5-di-
tert
-butylbenzene-1,2-diol) to 3,5-DTBQ dione (3,5-di-
tert
-butylcyclohexa-3,5-diene-1,2-dione).