Photocatalytic Oxygenation of Heterostilbenes—Batch versus Microflow Reactor

On the basis of earlier results with furan and thiophene derivatives benzobicyclo[3.2.1]octadiene, photocatalytic oxygenation novel furo- thieno heterostilbenes water-soluble manganese(III) porphyrins offered suitable possibilities to study their reactivities reaction pathways depending on heteroatom catalyst charge. The experiments were carried out in two reactors types (batch microflow) investigate geometric effects. NMR spectroscopy, GC, UPLC/MS analyses applied for identification quantification products. As our indicated, 2-thienyl common p-tolyl groups starting compounds remained intact due stronger aromaticity. Hence, derivative underwent only at open-chain part molecule, rates its reactions much lower than those furyl analogue. less stable ring was easily oxygenated, products highest ratios 2-furanon derivatives. Epoxide formation occurred parts both substrates preferably by anionic catalyst. Nevertheless, conversion higher cationic porphyrin, according electrophilic attacks photogenerated Mn(V)=O species. Additionally, significantly faster microflow more favorable circumstances mass transfer, diffusion, light penetration.