Fine-Bubble–Slug-Flow Hydrogenation of Multiple Bonds and Phenols
Takuya Iio, Kohei Nagai, Tomoki Kozuka, Akhtar Mst Sammi, Kohei Sato, Tetsuo Narumi, Nobuyuki Mase∗
We describe a promising method for the continuous hydrogenation of alkenes or alkynes by using a newly developed fine-bubble generator. The fine-bubble-containing slug-flow system was up to 1.4 times more efficient than a conventional slug-flow method. When applied in the hydrogenation of phenols to the corresponding cyclohexanones, the fine bubble–slug-flow method suppressed over-reduction. As this method does not require the use of excess gas, it is expected to be widely applicable in improving the efficiency of gas-mediated flow reactions.