10.1021/acs.inorgchem.5b01983.s003
Tiago A. Fernandes
Tiago A.
Fernandes
Carla I. M. Santos
Carla
I. M. Santos
Vânia André
Vânia
André
Julia Kłak
Julia
Kłak
Marina V. Kirillova
Marina V.
Kirillova
Alexander M. Kirillov
Alexander M.
Kirillov
Copper(II) Coordination Polymers Self-Assembled from
Aminoalcohols and Pyromellitic Acid: Highly Active Precatalysts for
the Mild Water-Promoted Oxidation of Alkanes
American Chemical Society
2016
EPR
coordination
acid
oxidation
XRD
2 D nets
precatalyst
medium
Hbea
H 2O
cycloalkane
spectroscopy
Cu
polymer
IR
H 2edea
2016-01-04 00:00:00
Dataset
https://acs.figshare.com/articles/dataset/Copper_II_Coordination_Polymers_Self_Assembled_from_Aminoalcohols_and_Pyromellitic_Acid_Highly_Active_Precatalysts_for_the_Mild_Water_Promoted_Oxidation_of_Alkanes/2092297
Three novel water-soluble 2D copper(II)
coordination polymers[{Cu<sub>2</sub>(μ<sub>2</sub>-dmea)<sub>2</sub>(H<sub>2</sub>O)}<sub>2</sub>(μ<sub>4</sub>-pma)]<sub><i>n</i></sub>·4<i>n</i>H<sub>2</sub>O (<b>1</b>), [{Cu<sub>2</sub>(μ<sub>2</sub>-Hedea)<sub>2</sub>}<sub>2</sub>(μ<sub>4</sub>-pma)]<sub><i>n</i></sub>·4<i>n</i>H<sub>2</sub>O (<b>2</b>), and [{Cu(bea)(Hbea)}<sub>4</sub>(μ<sub>4</sub>-pma)]<sub><i>n</i></sub>·2<i>n</i>H<sub>2</sub>O (<b>3</b>)were generated by
an aqueous medium self-assembly method from copper(II) nitrate, pyromellitic
acid (H<sub>4</sub>pma), and different aminoalcohols [<i>N</i>,<i>N</i>-dimethylethanolamine (Hdmea), <i>N</i>-ethyldiethanolamine (H<sub>2</sub>edea), and <i>N</i>-benzylethanolamine
(Hbea)]. Compounds <b>2</b> and <b>3</b> represent the
first coordination polymers derived from H<sub>2</sub>edea and Hbea.
All the products were characterized by infrared (IR), electron paramagnetic
resonance (EPR), and ultraviolet–visible light (UV-vis) spectroscopy,
electrospray ionization–mass spectroscopy (ESI-MS(±)),
thermogravimetric and elemental analysis, and single-crystal X-ray
diffraction (XRD), which revealed that their two-dimensional (2D)
metal–organic networks are composed of distinct dicopper(II)
or monocopper(II) aminoalcoholate units and μ<sub>4</sub>-pyromellitate
spacers. From the topological viewpoint, the underlying 2D nets of <b>1</b>–<b>3</b> can be classified as uninodal 4-connected
layers with the <b>sql</b> topology. The structures of <b>1</b> and <b>2</b> are further extended by multiple intermolecular
hydrogen bonds, resulting in three-dimensional (3D) hydrogen-bonded
networks with rare or unique topologies. The obtained compounds also
act as highly efficient precatalysts for the mild homogeneous oxidation,
by aqueous H<sub>2</sub>O<sub>2</sub> in acidic MeCN/H<sub>2</sub>O medium, of various cycloalkanes to the corresponding alcohols and
ketones. Overall product yields up to 45% (based on cycloalkane) were
attained and the effects of various reaction parameters were investigated,
including the type of precatalyst and acid promoter, influence of
water, and substrate scope. Although water usually strongly inhibits
the alkane oxidations, a very pronounced promoting behavior of H<sub>2</sub>O was detected when using the precatalyst <b>1</b>,
resulting in a 15-fold growth of an initial reaction rate in the cyclohexane
oxidation on increasing the amount of H<sub>2</sub>O from ∼4
M to 17 M in the reaction mixture, followed by a 2-fold product yield
growth.