Atkanesulfonate monooxygenase SsuD facilitates the desulfonation reaction of alkane sulfonates to release sulfite and corresponding aldehydes/ketones. Oxygen is activated by the reduced flavin. One oxygen atom is to f...Atkanesulfonate monooxygenase SsuD facilitates the desulfonation reaction of alkane sulfonates to release sulfite and corresponding aldehydes/ketones. Oxygen is activated by the reduced flavin. One oxygen atom is to fi＇om water and the other oxygen atom is to from aldehydes/ketones. The oxidized flavin is regenerated after water is formed. The chemical biomimetic system was established according to the preliminary mechanism of alkanesulfonate monooxygenase and the cyclic mechanism was proposed for the formation ofaldehydes/ketones. Two oxygen atoms from the reduced flavin to form C（4a）-peroxy-flavin. The oxygen atom connected with C（4a） abstracts one electron from the neighbouring oxygen to transfer one oxygen atom to C1 ofalkanesulfonates and abstracts one hydrogen from C1 ofalkanesulfonates to break C 1-H bond. Hydroxy-flavin was produced by the above cyclic mechanism. Alkansulfonate monooxygenase SsuD does not directly involve in the reaction. It only supplies some comfortable environment to facilitate the target reactiorL展开更多
Blue light-emitting polyfluorenes containing dibenzothiophene-S,S-dioxide(SO) unit in alkyl side chain(PF-FSOs and PF-CzSOs) were synthesized. All the polymers show high thermal stability with the decomposition temper...Blue light-emitting polyfluorenes containing dibenzothiophene-S,S-dioxide(SO) unit in alkyl side chain(PF-FSOs and PF-CzSOs) were synthesized. All the polymers show high thermal stability with the decomposition temperatures over400 °C. The highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) energy levels of the copolymer slightly decrease with the increase of SO content in side chain. PL spectra of the polymers show slightly red shift and broadening with the increase of solvent polarities, indicating unremarkable intramolecular charge transfer(ICT) effect in the polymers containing SO unit in alkyl side chain. EL spectra of the polymers are almost unchanged in the current densities from 100 to 400 mA cm.2, indicating the superb EL stability of the resulted polymers. The EL spectra of the copolymers exhibit obvious blue-shift and narrowing with the CIE of(0.18, 0.11) for PF-FSO10 and(0.17, 0.11) for PF-CzSO10, respectively,compared with PF-SO10 containing SO unit in main chain with the CIE of(0.16, 0.17) and PFO with the CIE of(0.18, 0.18).The superior device performances were obtained with the luminous efficiency(LEmax) of 1.17 and 0.68 cd A.1 for PF-FSO15 and PF-CzSO20, respectively, compared with the LEmax of 0.37 cd A.1 for PFO. The results indicate that linking SO unit to alkyl side chain of the polyfluorene is a promising strategy for efficient blue light-emitting polymers.展开更多
文摘Atkanesulfonate monooxygenase SsuD facilitates the desulfonation reaction of alkane sulfonates to release sulfite and corresponding aldehydes/ketones. Oxygen is activated by the reduced flavin. One oxygen atom is to fi＇om water and the other oxygen atom is to from aldehydes/ketones. The oxidized flavin is regenerated after water is formed. The chemical biomimetic system was established according to the preliminary mechanism of alkanesulfonate monooxygenase and the cyclic mechanism was proposed for the formation ofaldehydes/ketones. Two oxygen atoms from the reduced flavin to form C（4a）-peroxy-flavin. The oxygen atom connected with C（4a） abstracts one electron from the neighbouring oxygen to transfer one oxygen atom to C1 ofalkanesulfonates and abstracts one hydrogen from C1 ofalkanesulfonates to break C 1-H bond. Hydroxy-flavin was produced by the above cyclic mechanism. Alkansulfonate monooxygenase SsuD does not directly involve in the reaction. It only supplies some comfortable environment to facilitate the target reactiorL
基金supported by the National Key Basic Research and Development Program of China (2015CB655004)the National Natural Science Foundation of China (51473054, 91333206)the Fundamental Research Funds for the Central Universities, South China of Technology (2017MS020)
文摘Blue light-emitting polyfluorenes containing dibenzothiophene-S,S-dioxide(SO) unit in alkyl side chain(PF-FSOs and PF-CzSOs) were synthesized. All the polymers show high thermal stability with the decomposition temperatures over400 °C. The highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) energy levels of the copolymer slightly decrease with the increase of SO content in side chain. PL spectra of the polymers show slightly red shift and broadening with the increase of solvent polarities, indicating unremarkable intramolecular charge transfer(ICT) effect in the polymers containing SO unit in alkyl side chain. EL spectra of the polymers are almost unchanged in the current densities from 100 to 400 mA cm.2, indicating the superb EL stability of the resulted polymers. The EL spectra of the copolymers exhibit obvious blue-shift and narrowing with the CIE of(0.18, 0.11) for PF-FSO10 and(0.17, 0.11) for PF-CzSO10, respectively,compared with PF-SO10 containing SO unit in main chain with the CIE of(0.16, 0.17) and PFO with the CIE of(0.18, 0.18).The superior device performances were obtained with the luminous efficiency(LEmax) of 1.17 and 0.68 cd A.1 for PF-FSO15 and PF-CzSO20, respectively, compared with the LEmax of 0.37 cd A.1 for PFO. The results indicate that linking SO unit to alkyl side chain of the polyfluorene is a promising strategy for efficient blue light-emitting polymers.
