Loading…
Discrete mononuclear and dinuclear compounds containing a MoO22+ core and 4-aminobenzhydrazone ligands: synthesis, structure and organic-solvent-free epoxidation activityElectronic supplementary information (ESI) available: (1) Scheme, (2), powder diffraction patterns, (3) figures for compounds, (4) tables of selected bond distances and angles and of hydrogen bond parameters and (5) spectral data. Crystallographic data sets for the structures 1a, 1c, 2-β, 2a, 2b-α, 2b-β, 3c, 2-α and 3. CCDC 1861
Cyclic dinuclear molybdenum(vi) complexes [MoO 2 (L 1-3 )] 2 ( 1 , 2-α , 2-β and 3 ) were synthesized through the use of coordination-driven self-assembly of a MoO 2 2+ core and 4-aminobenzoylhydrazone ligands (salicylaldehyde (H 2 L 1 ), 3-methoxysalicylaldehyde (H 2 L 2 ) or 4-methoxysalicylaldehy...
Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Cyclic dinuclear molybdenum(vi) complexes [MoO
2
(L
1-3
)]
2
(
1
,
2-α
,
2-β
and
3
) were synthesized through the use of coordination-driven self-assembly of a MoO
2
2+
core and 4-aminobenzoylhydrazone ligands (salicylaldehyde (H
2
L
1
), 3-methoxysalicylaldehyde (H
2
L
2
) or 4-methoxysalicylaldehyde 4-aminobenzoylhydrazone (H
2
L
3
)). Their X-ray diffraction (XRD) analysis revealed that these types of ligands could serve as organic linkers for
cis
-octahedral complexes containing a MoO
2
2+
core. Mononuclear complexes [MoO
2
(L
1-3
)(MeOH)] (
1a-3a
) and [MoO
2
(L
1-3
)(EtOH)] (
1b
,
2b-α
,
2b-β
and
3b
) were also obtained. In the presence of strong donors, such as dmf, ligand substitution occurred and the structures of
1-3
changed into [MoO
2
(L
1
)(dmf)] (
1c
), [MoO
2
(L
2
)(dmf)] (
2c
) and [MoO
2
(L
3
)(H
2
O)]·dmf (
3c·dmf
), respectively. The dioxidomolybdenum(
vi
) complexes were tested for catalytic epoxidation of cyclooctene under eco-friendly reaction conditions by using aqueous
tert
-butyl hydroperoxide (TBHP) as an oxidant without the addition of an organic solvent. The present study showed much better activity of the dinuclear catalysts than the mononuclear ones due to the weak donor properties of the amino group and high geometric constraints occurring in such small sized self-assembled systems as confirmed by density functional theory calculations.
New aroylhydrazone molybdenum(
vi
) complexes have been synthesized, characterized and used as (pre)catalysts for epoxidation of cyclooctene using aqueous TBHP as the oxidant. |
|---|---|
| ISSN: | 1144-0546 1369-9261 |
| DOI: | 10.1039/c8nj04074e |