Improved Reactor Productivity for the Safe Photo‐Oxidation of Citronellol Under Visible Light LED Irradiation. Issue 3 (11th January 2019)

• Record Type: Journal Article
• Authors: Hamami, Zine Eddine; Vanoye, Laurent; Fongarland, Pascal; de Bellefon, Claude; Favre‐Réguillon, Alain
• Is Part Of: ChemPhotoChem. Volume 3:Issue 3(2019)
• Page Start: 122
• Page End: 128
• Publication Date: 2019-01-11
• Subjects: citronellol -- flow chemistry -- microreactors -- photo-oxidation -- singlet oxygen; Photochemistry -- Periodicals; Periodicals; Electronic journals; 541.35
• DOI: 10.1002/cptc.201800201
• Languages: English
• ISSNs: 2367-0932

Abstract

Abstract: A simple continuous flow photochemical reactor was optimized for the safe photo‐oxidation of citronellol into precursors of rose oxide, a flagrance of commercial value. The reactor productivity was increased by a factor of 4 compared to the current literature for a conversion above 99 % and in safe conditions (up to 0.72 mM min −1 mLreactor −1 ). The reactor was based on a classical design described by Booker‐Milburn et al., i. e. multiple loops of perfluoroalkoxy (PFA) tubing wrapped tightly around a visible LED lamp under slug flow conditions. The influence of the type of visible white LED light (6500 K vs. 3000 K), of photosensitizers (tetraphenylporphyrin vs. methylene blue), of solvent (CH2 Cl2 vs. MeOH), concentration of citronellol (0.1 M vs. 2 M) and of mass efficiency of the reactors (PFA tubing of 0.75 mm to 0.25 mm) was paramount to increase the productivity of the reactor. Abstract : Go blue : An improvement of reactor productivity for the photo‐oxidation of citronellol is reported. Optimisation of the visible light LED and improvement of O2 mass transfer efficiency enables the use of methylene blue in MeOH for a safe and efficient preparation of rose oxide. Under these conditions, reactor productivity was increase by a factor of four compared to the current literature.