Synthesis of chiral Mn(III)-meso-tetrakis-[2.2]-p-cyclophanyl-porphyrin: A new catalyst for enantioselective epoxidation
Articolo
Data di Pubblicazione:
1996
Citazione:
Synthesis of chiral Mn(III)-meso-tetrakis-[2.2]-p-cyclophanyl-porphyrin: A new catalyst for enantioselective epoxidation / S. Banfi, A. Manfredi, F. Montanari, G. Pozzi, S. Quici. - In: JOURNAL OF MOLECULAR CATALYSIS. A: CHEMICAL. - ISSN 1381-1169. - 113:1-2(1996 Nov), pp. 77-86.
Abstract:
he synthesis of Mn(III)-complexes of new chiral porphyrins 1a and 1b prepared by condensation of enantiomerically pure [2.2]-p-cyclophane-4-carbaldehyde and pyrrole are described. These compounds were used as catalysts in epoxidation reactions of prochiral alkenes, carried out in the presence of aqueous NaOCl at pH = 10.0 as oxygen donor and small amounts of 4-tert-butylpyridine as axial ligand, in CH2Cl2/H2O two-phase conditions at 0 degrees C. Results indicate a satisfactory catalytic efficiency (up to 700 overall turnovers), with enantiomeric excesses in the range 22-31%.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
ASYMMETRIC EPOXIDATIONS; MN(III) PORPHYRINS; 2-PHASE CONDITIONS; AXIAL LIGAND; MESO-<2.2>PARACYCLOPHANYLTRIPHENYLPORPHYRIN; METALLOPORPHYRINS; OXIDATIONS; RESOLUTION; HOCL
Elenco autori:
S. Banfi, A. Manfredi, F. Montanari, G. Pozzi, S. Quici
Link alla scheda completa: