Photooxidation of Benzyl Alcohols with Immobilized Flavins

Schmaderer, Harald and Hilgers, Petra and Lechner, Robert and Koenig, Burkhard (2009) Photooxidation of Benzyl Alcohols with Immobilized Flavins. ADVANCED SYNTHESIS & CATALYSIS, 351 (1-2). pp. 163-174. ISSN 1615-4150, 1615-4169

Full text not available from this repository. (Request a copy)

Abstract

Benzyl alcohols are oxidized cleanly and efficiently to the corresponding aldehydes under irradiation using flavin photocatalysts and aerial oxygen as the terminal oxidant in homogeneous aqueous solution. Turnover frequencies (TOF) of more than 800 h(-1) and turnover numbers (TON) of up to 68 were obtained. Several flavin photocatalysts with fluorinated or hydrophobic aliphatic chains were immobilized on solid supports like fluorous silica gel, reversed phase silica gel or entrapped in polyethylene pellets. The catalytic efficiency of the heterogeneous photocatalysts was studied for the oxidation of different benzyl alcohols in water and compared to the analogous homogeneous reactions. Removal of the heterogeneous photocatalyst stops the reaction conversion immediately, which shows that the immobilized flavin is the catalytically active species. The immobilized catalysts are stable, retain their reactivity if compared to the corresponding homogeneous systems and are easily removed from the reaction mixture and reused. TOF of up to 26 h(-1), TON of 280 and up to 3 reaction cycles without loss of activity are possible with the heterogeneous flavin photocatalysts.

Item Type: Article
Uncontrolled Keywords: FLUOROUS BIPHASIC CATALYSIS; MODEL SYSTEMS; FLAVOENZYME ACTIVITY; HYDROGEN-PEROXIDE; ELECTRON-TRANSFER; MOLECULAR-OXYGEN; OXIDATION; DERIVATIVES; RIBOFLAVIN; EFFICIENT; catalyst recycling; flavins; fluorous chemistry; immobilization; photooxidation; redox chemistry
Subjects: 500 Science > 540 Chemistry & allied sciences
Divisions: Chemistry and Pharmacy > Institut für Organische Chemie
Chemistry and Pharmacy > Institut für Organische Chemie > Lehrstuhl Prof. Dr. Burkhard König
Depositing User: Dr. Gernot Deinzer
Date Deposited: 08 Oct 2020 11:38
Last Modified: 08 Oct 2020 11:38
URI: https://pred.uni-regensburg.de/id/eprint/29602

Actions (login required)

View Item View Item