摘要
A practical catalytic method to oxidize α-ionone with molecular oxygen using N-hydroxyphthalimide(NHPI)combined with acetylacetone cobatt(Ⅱ)(Co(acac)2)was developed,and the probable catalytic mechanism was proposed.The influences of the reaction conditions on conversion of α-ionone and the selectivity of the major product(5-keto-α-ionone)were investigated,and the technical parameters for 5-keto-α-ionone were optimized.The results show that the primary product is 5-keto-α-ionone,and by-products include epoxy-α-ionone,as well as rearrangement products 4-keto-β-ionone and epoxy-β-ionone,which are characterized by infrared spectra,proton nuclear magnetic resonance spectra,mass spectra and elemental analysis.The selectivity of 5-keto-α-ionone and the conversion of α-ionone are 55.0% and 97.0%,respectively,when 30%(molar fraction)NHPI,1.0%(molar fraction)Co(acac)2 and no solvent are employed under O2 pressure of 1.0 MPa and the reaction temperature of 65℃for 11 h.The procedure shows good reproducibility in the parallel experiments.
A practical catalytic method to oxidize α-ionone with molecular oxygen using N-hydroxyphthalimide（NHPI） combined with acetylacetone cobatt（ Ⅱ ） （Co（acac）2） was developed, and the probable catalytic mechanism was proposed. The influences of the reaction conditions on conversion of α-ionone and the selectivity of the major product （5-keto-α-ionone） were investigated, and the technical parameters for 5-keto-α-ionone were optimized. The results show that the primary product is 5-keto-α-ionone, and by-products include epoxy-α-ionone, as well as rearrangement products 4-keto-β-ionone and epoxy-β-ionone, which are characterized by infrared spectra, proton nuclear magnetic resonance spectra, mass spectra and elemental analysis. The selectivity of 5-keto-α-ionone and the conversion of α-ionone are 55.0% and 97.0%, respectively, when 30%（molar fraction） NHPI, 1.0%（molar fraction） Co（acac）2 and no solvent are employed under O2 pressure of 1.0 MPa and the reaction temperature of 65 ℃ for 11 h. The procedure shows good reproducibility in the parallel experiments.
基金
Project(50573019)supported by the National Natural Science Foundation of China
