Use of phase transfer agents for photocyanation of aromatic hydrocarbons

A laser trapping-spectroscopy study on the photocyanation of perylene across a single micrometre-sized oil droplets/water interface: droplet-size effects on photoreaction quantum yield

“…Indeed, Beugelmans et al reported that the photocyanation yields of nitroaromatics in a methylene chloride/water/KCN system were improved by adding tetrabutylammonium cyanide as a catalyst. 43,44 If ion pair formation between a dodecyltrimethylammonium cation and a cyanide anion proceeds and the ion pairs distribute to the oil phase to some extent, the photoreaction takes place partly in the oil droplet, leading to the increase in the reaction efficiency. Therefore, we consider that the surfactant effects on F CN originate from cooperative effects by formation of the electric double layer at the interface and ion pair extraction of cyanide ions to the oil phase.…”

A Mechanistic Study of Photocyanation of Pyrene in Oil-in-Water Emulsion Systems

“…Besides the electrical double layer effects, we suppose that DTAC acts as a phase-transfer catalyst. Indeed, Beugelmans et al reported that the photocyanation yield of nitroaromatics in methylene chloride/water (KCN as a reagent) could be improved by adding tetra- n -butylammonium cyanide . If ion pair formation between a dodecyltrimethylammonium cation and a cyanide anion proceeds in the present system and the ion pairs distribute to the oil droplets to some extent, the cyanation reaction in eq 4 would take place partly in the droplet interior, causing the increase in the reaction efficiency.…”

“…After these reports, various attempts have been conducted to improve the reaction yield. As an example, Beugelmans et al reported that the product yield could be improved by using aprotic solvent−crown ether combinations to dissolve alkali cyanide as well as by employing a phase-transfer catalyst . The efficiency of photocyanation reaction is also dependent on the number of the aromatic rings ArH.…”

Temperature-sensitive photochemical aromatic substitution on 4-nitroanisole

“…Applications of a PTC technique in photochemistry are quite rare. 15-19,34, 35 Beugelmans et al 36,37 have reported an interesting synthetic example dealing with the photocyanation reactions of aromatic hydrocarbons with KCN and a crown ether or tetrabutylammonium cyanide in a water-dichloromethane system. We recently studied the effect of addition of an ammonium salt, serving as a surfactant, into the two-phase reaction system.…”