Bizaia N, de Faria EH, Ricci GP, Calefi PS, Nassar EJ, Castro KADF, Nakagaki S, Ciuffi KJ, Trujillano R, Vicente MA, Gil A, Korili SA. Porphyrin-kaolinite as efficient catalyst for oxidation reactions.
ACS APPLIED MATERIALS & INTERFACES 2009;
1:2667-78. [PMID:
20356141 DOI:
10.1021/am900556b]
[Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The preparation, characterization, and application in oxidation reactions of new biomimetic catalysts are reported. Brazilian Sao Simao kaolinite clay has been functionalized with [meso-tetrakis(pentafluorophenyl)porphinato]iron(III), Fe(TPFPP). To obtain the functionalized clay, the natural clay was purified by dispersion-sedimentation, expanded by insertion of dimethyl sulfoxide (DMSO), and functionalized with amino groups by substitution of DMSO with ethanolamine. These previous steps allowed clay functionalization with Fe(TPFPP), leading to a layered material with a basal spacing of 10.73 A. Clay functionalization with the porphyrin was confirmed by formation of the secondary amine, as demonstrated by FTIR bands at 3500-3700 cm(-1). UV-vis spectroscopy revealed a red shift in the Soret band of the iron porphyrin in the functionalized material as compared to the parent iron porphyrin catalyst in solution, indicating Fe(III)P --> Fe(II)P reduction. The catalytic performance of the functionalized clay was evaluated in the epoxidation of cyclooctene, with complete selectivity for the epoxide (100% epoxide yield), and ketonization of cyclohexane, cyclohexanone being the major product. The novel catalyst was also evaluated in the Baeyer-Villiger (BV) oxidation of cyclohexanone, with 85% conversion of cyclohexanone in epsilon-caprolactone, with total selectivity to epsilon-caprolactone.
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