Abstract
A novel chiral sulphonato-salen-manganese(III) complex has been intercalated into a Zn(II)-Al(III) layered double hydroxide (LDH) host to produce a stable heterogeneous epoxidation catalyst. Powder X-ray diffraction, IR and UV-Visible ( solid) spectroscopy and TGA confirmed the successful intercalation of the Mn complex within the LDH gallery height. The intercalated sulphonato-salen-manganese(III) complex was found to be an effective heterogeneous catalyst for the stereoselective epoxidation of R-(+)-limonene and (-)-alpha-pinene at room temperature and using molecular oxygen at atmospheric pressure as oxidant. At close to 100% conversion, R-(+)- limonene was converted into the corresponding epoxide with 93% selectivity and 43% de (diastereomeric excess), whereas (-)-alpha-pinene was converted with 93% selectivity and 98% de. The catalyst could be recycled without loss of efficiency.
Original language | English |
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Pages (from-to) | 119-125 |
Number of pages | 6 |
Journal | Catalysis Letters |
Volume | 95 |
DOIs | |
Publication status | Published - 2004 |
Keywords
- chiral salen-manganese(III)
- layered double hydroxide
- LDH host catalyst
- R-(+)-limonene
- (-)-alpha-pinene
- epoxidation, heterogeneous catalysis
- HETEROGENEOUS ENANTIOSELECTIVE CATALYST
- NONFUNCTIONALIZED ALKENES
- ASYMMETRIC EPOXIDATION
- COMPLEXES
- HYDROTALCITE
- OLEFINS
- NICKEL
- OXIDATION