New copper(II) salicylaldimine derivatives for mild oxidation of cyclohexane
(2018) In Journal of Chemical Sciences 130(6).- Abstract
Abstract: Two new salicylaldiminato-copper(II) complexes, [Cu(L1)2] (1) and [Cu(L2)2] (2) (where HL1= 4 -tert-Butyl-2-[(thiophen-2-ylmethylimino)-methyl]-phenol and HL2= 2 , 4 -Di-tert-butyl-6-[(thiophen-2-ylmethylimino)-methyl]-phenol), endowed with a pendant thiophenyl moiety, were synthesized and characterized using standard spectroscopic techniques (FT-IR, UV-Vis, MS) and elemental analysis. Complexes 1 and 2 were unequivocally characterized by single crystal X-ray crystallography, which confirmed bidentate bis-chelation of the deprotonated -L1 and -L2 ligands to the copper (II) centres via the phenoxo and imine atoms forming square planar complexes. The copper(II)-hydroperoxo derivatives... (More)
Abstract: Two new salicylaldiminato-copper(II) complexes, [Cu(L1)2] (1) and [Cu(L2)2] (2) (where HL1= 4 -tert-Butyl-2-[(thiophen-2-ylmethylimino)-methyl]-phenol and HL2= 2 , 4 -Di-tert-butyl-6-[(thiophen-2-ylmethylimino)-methyl]-phenol), endowed with a pendant thiophenyl moiety, were synthesized and characterized using standard spectroscopic techniques (FT-IR, UV-Vis, MS) and elemental analysis. Complexes 1 and 2 were unequivocally characterized by single crystal X-ray crystallography, which confirmed bidentate bis-chelation of the deprotonated -L1 and -L2 ligands to the copper (II) centres via the phenoxo and imine atoms forming square planar complexes. The copper(II)-hydroperoxo derivatives of 1 and 2 ([(L1)2CuII-OOH] (3) and [(L2)2CuII-OOH] (4)) were also synthesized and the formation of the active intermediate in solution studied. Complexes 1 and 2 were tested as catalyst precursors in cyclohexane oxidation under mild reaction conditions using hydrogen peroxide (H 2O 2) as a terminal oxidant, and were found to catalyse oxidation of the substrate with yields comparable to similar mononuclear and even multinuclear copper complexes. Graphical Abstract: Synopsis Synthesis, characterisation, and molecular structure of salicylaldiminato-copper(II) complexes, and their catalytic evaluation in the oxidation of cyclohexane employing hydrogen peroxide as a terminal oxidant have been studied. The complexes catalysed conversion of cyclohexane with appreciable yields. [Figure not available: see fulltext.].
(Less)
- author
- Busa, Asanda V. ; Lalancette, Roger ; Nordlander, Ebbe LU and Onani, Martin
- organization
- publishing date
- 2018-06-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Copper, cyclohexane, hydroperoxo complex, oxidation
- in
- Journal of Chemical Sciences
- volume
- 130
- issue
- 6
- article number
- 59
- publisher
- Indian Academy of Sciences
- external identifiers
-
- scopus:85047461224
- ISSN
- 0974-3626
- DOI
- 10.1007/s12039-018-1455-y
- language
- English
- LU publication?
- yes
- id
- 6002c70f-757c-43e1-9fbd-8fcdd8bf6b94
- date added to LUP
- 2018-06-05 10:34:57
- date last changed
- 2022-03-25 02:15:12
@article{6002c70f-757c-43e1-9fbd-8fcdd8bf6b94, abstract = {{<p>Abstract: Two new salicylaldiminato-copper(II) complexes, [Cu(L1)2] (1) and [Cu(L2)2] (2) (where HL<sup>1</sup>= 4 -tert-Butyl-2-[(thiophen-2-ylmethylimino)-methyl]-phenol and HL<sup>2</sup>= 2 , 4 -Di-tert-butyl-6-[(thiophen-2-ylmethylimino)-methyl]-phenol), endowed with a pendant thiophenyl moiety, were synthesized and characterized using standard spectroscopic techniques (FT-IR, UV-Vis, MS) and elemental analysis. Complexes 1 and 2 were unequivocally characterized by single crystal X-ray crystallography, which confirmed bidentate bis-chelation of the deprotonated -L<sup>1</sup> and -L<sup>2</sup> ligands to the copper (II) centres via the phenoxo and imine atoms forming square planar complexes. The copper(II)-hydroperoxo derivatives of 1 and 2 ([(L1)2CuII-OOH] (3) and [(L2)2CuII-OOH] (4)) were also synthesized and the formation of the active intermediate in solution studied. Complexes 1 and 2 were tested as catalyst precursors in cyclohexane oxidation under mild reaction conditions using hydrogen peroxide (H <sub>2</sub>O <sub>2</sub>) as a terminal oxidant, and were found to catalyse oxidation of the substrate with yields comparable to similar mononuclear and even multinuclear copper complexes. Graphical Abstract: Synopsis Synthesis, characterisation, and molecular structure of salicylaldiminato-copper(II) complexes, and their catalytic evaluation in the oxidation of cyclohexane employing hydrogen peroxide as a terminal oxidant have been studied. The complexes catalysed conversion of cyclohexane with appreciable yields. [Figure not available: see fulltext.].</p>}}, author = {{Busa, Asanda V. and Lalancette, Roger and Nordlander, Ebbe and Onani, Martin}}, issn = {{0974-3626}}, keywords = {{Copper; cyclohexane; hydroperoxo complex; oxidation}}, language = {{eng}}, month = {{06}}, number = {{6}}, publisher = {{Indian Academy of Sciences}}, series = {{Journal of Chemical Sciences}}, title = {{New copper(II) salicylaldimine derivatives for mild oxidation of cyclohexane}}, url = {{http://dx.doi.org/10.1007/s12039-018-1455-y}}, doi = {{10.1007/s12039-018-1455-y}}, volume = {{130}}, year = {{2018}}, }